From bc7baea7c43a19992e1d9945773888f8ef81d3ce Mon Sep 17 00:00:00 2001
From: khodowany <khodowany@proton.me>
Date: Thu, 8 Oct 2026 02:13:45 -0500
Subject: [PATCH] Cleanup

---
 TECHNICAL_GUIDE.md                        |    10 +
 generator/__main__.py                     |    22 +-
 generator/arrange/accompaniment.py        |    11 +-
 generator/arrange/assembly.py             |   100 +
 generator/arrange/ending.py               |    32 +-
 generator/arrange/ending_plan.py          |    22 +
 generator/arrange/form.py                 |    58 +
 generator/arrange/generate.py             |    40 +-
 generator/audio_assets.py                 |    68 +
 generator/cache.py                        |    82 +
 generator/catalog.py                      |     6 +-
 generator/chord_families.py               |    14 +-
 generator/comping.py                      |    68 +-
 generator/comping_rhythm.py               |    23 +-
 generator/compose.py                      |    13 +-
 generator/composition.py                  |   158 +
 generator/composition_types.py            |    28 +
 generator/engraving/cache.py              |    44 +-
 generator/engraving/layout.py             |     6 +-
 generator/engraving/pipeline.py           |   196 +-
 generator/engraving/worker.py             |   190 +
 generator/guitar.py                       |    44 +-
 generator/model.py                        |   156 -
 generator/musicxml.py                     |     3 +-
 generator/musicxml_writer.py              |     3 +-
 generator/parts.py                        |     1 -
 generator/performance.py                  |    62 +-
 generator/printing.py                     |    22 +-
 generator/production.py                   |   345 +-
 generator/role_cache.py                   |    29 +
 generator/score.py                        |    59 +-
 generator/score_io.py                     |    59 +
 generator/solo/authored.py                |    27 +-
 generator/solo/composer.py                |    31 +-
 generator/solo/decoder.py                 |    36 +-
 generator/solo/expressions.py             |    39 +-
 generator/solo/harmonic.py                |    17 +-
 generator/solo/profiles.py                |     3 +-
 generator/solo/recognition.py             |    26 +-
 generator/solo/report.py                  |    19 +-
 generator/{solo/analysis.py => source.py} |    40 +-
 generator/summary.py                      |     3 +-
 generator/train.py                        |    21 +-
 generator/validation.py                   |   161 +
 generator/vocabulary.py                   |    48 +-
 include/vamp_zero/score_loader.hpp        |     3 +-
 include/vamp_zero/ui.hpp                  |     3 +-
 src/vamp_zero/app.cpp                     |     7 +-
 src/vamp_zero/score_loader.cpp            |    20 +-
 src/vamp_zero/ui.cpp                      |     6 +-
 tests/CMakeLists.txt                      |     5 +
 tests/asset_contract.py                   |    17 +
 tests/fixtures/assets_manifest.json       |   411 +
 tests/fixtures/role_outputs.json          | 16725 ++++++++++++++++++++
 tests/production_fixtures.py              |     5 +-
 tests/solo_fixtures.py                    |     4 +-
 tests/test_acoustic.py                    |    10 +-
 tests/test_acoustic_pairs.py              |     3 +-
 tests/test_acoustic_voicing.py            |     7 +-
 tests/test_arrangement_ending.py          |    12 +-
 tests/test_arrangement_pickup.py          |    12 +-
 tests/test_catalog.py                     |     4 +-
 tests/test_chord_families.py              |    11 +-
 tests/test_comping_cycles.py              |    22 +-
 tests/test_comping_meters.py              |    19 +-
 tests/test_comping_rhythm.py              |    23 +-
 tests/test_comping_voicings.py            |    33 +-
 tests/test_electric_voicing.py            |     4 +-
 tests/test_engraving_cache.py             |     9 +-
 tests/test_fret_policy.py                 |    21 +-
 tests/test_generator_boundaries.py        |    64 +
 tests/test_guitar.py                      |    16 +-
 tests/test_guitar_parts.py                |    11 +-
 tests/test_harmonic_recognition.py        |     6 +-
 tests/test_harmony.py                     |     1 -
 tests/test_independent_generation.py      |    54 +-
 tests/test_key_metadata.py                |     3 +-
 tests/test_learned_solos.py               |    24 +-
 tests/test_music_model.py                 |    13 +-
 tests/test_output_contract.py             |    20 +
 tests/test_parts.py                       |    17 +-
 tests/test_performance.py                 |    13 +-
 tests/test_printing.py                    |     7 +-
 tests/test_publish_package.py             |    12 +-
 tests/test_score_bundle.py                |    30 +-
 tests/test_score_loader.cpp               |    33 +
 tests/test_six_parts.py                   |    11 +-
 tests/test_voicing.py                     |     3 +-
 88 files changed, 18844 insertions(+), 1335 deletions(-)
 create mode 100644 generator/arrange/assembly.py
 create mode 100644 generator/arrange/ending_plan.py
 create mode 100644 generator/audio_assets.py
 create mode 100644 generator/cache.py
 create mode 100644 generator/composition.py
 create mode 100644 generator/composition_types.py
 create mode 100644 generator/engraving/worker.py
 create mode 100644 generator/role_cache.py
 create mode 100644 generator/score_io.py
 rename generator/{solo/analysis.py => source.py} (56%)
 create mode 100644 generator/validation.py
 create mode 100644 tests/asset_contract.py
 create mode 100644 tests/fixtures/assets_manifest.json
 create mode 100644 tests/fixtures/role_outputs.json
 create mode 100644 tests/test_generator_boundaries.py
 create mode 100644 tests/test_output_contract.py

diff --git a/TECHNICAL_GUIDE.md b/TECHNICAL_GUIDE.md
index b4bcd12..0a5c3f0 100644
--- a/TECHNICAL_GUIDE.md
+++ b/TECHNICAL_GUIDE.md
@@ -49,6 +49,8 @@ The Zero menus use direct taps: release on a row to select it, tap switches to t
 
 In score view, Zero and Pico share one gesture state machine: a second release within 220 ms of the first release produces previous, a hold of at least 700 ms produces select once, and other taps produce next. A late second release preserves both single taps; holding consumes a pending first tap. Zero schedules pending-tap deadlines without polling and discards canceled or obsolete timer callbacks.
 
+Score loading uses a dedicated single-worker executor for SQLite reads and JSON parsing. Completion returns to the control executor. The loader retains one in-flight request, coalesces pending selections, and discards stale results, keeping database work off HTTP and playback polling.
+
 ## Score Generation
 
 The build runs `./modulus.py python -m generator` against `data/` and writes build-only assets under the CMake binary tree. Every song produces acoustic, electric, and vocal parts in its authored musical key. Source counts are discovered, not fixed in code. Generator-only optional chord markers are consumed before publishing.
@@ -59,6 +61,14 @@ The pipeline is Soundslice/MuseScore -> uncompressed `.xml` -> musical model and
 
 ### Musical Data
 
+Generator dependencies run from pure musical values and source analysis toward composition, assembly, and publication. `model` contains primitive values; `validation` checks score documents; `score` contains pure score operations; and `score_io` owns bundle/file validation. `source` owns canonical source identity and immutable source events. `arrange.form.FormPlan` supplies source-derived sections, ownership windows, and pickup stops to both accompaniment and role assembly.
+
+`composition` generates one role from an explicit immutable `vocabulary.CompositionContext`; `production` schedules typed worker requests and publishes the assembled parts. Lower musical functions receive that context explicitly. The scoped vocabulary API remains available for standalone callers and tests. Cached vocabulary loads return owned copies so one caller cannot alter another caller's resources.
+
+Role cache identities include the transitive generator imports of the composition entrypoint. Engraving cache identities similarly include renderer dependencies. Cache identities never seed musical choices. `cache` provides shared content identity and staged-file publication mechanics, while role, PNG, and PDF adapters retain their own validation. `engraving.worker` owns rendering and its bounded image cache; `engraving.pipeline` groups and schedules work. `performance` contains pure timing contracts, and `audio_assets` validates and copies supplied recordings.
+
+The reviewed output contract is checked by `tests.test_output_contract` for complete synthetic role scores, including learned solos, and by `python -m tests.asset_contract <generated-assets-directory>` for every non-diagnostic asset. CTest runs the asset check against the normal build output. Musical output, JSON/catalog serialization, PNGs, and PDFs must remain unchanged during structural refactors; diagnostic text and cache identities may change.
+
 `data/songs/` contains authoritative source scores. `data/training/manifest.json` pairs each authored solo with a source and a slot (1 or 2), and declares its pitch convention. Both slots train **one pooled model**. Slot 1 maps to acoustic playback and slot 2 to electric playback; slot and instrument names are not model features. The four XML files retain their notes, harmony, timing, ties, rests, Autumn Leaves pickup and All of Me's full-bar opening. Explanatory labels such as `Lead in`, `b9` and `6` were removed; they were not model features. Written chord extensions remain intact.
 
 `data/models/solo.json` is an explicitly trained, versioned statistical model. Its short-context counts, rhythm and register statistics are learned from the paired examples. Provenance records input hashes and the training version. This is supervised use of the supplied solos, not independence from them and not a neural network pretrained on an external corpus.
diff --git a/generator/__main__.py b/generator/__main__.py
index d950ba4..3416cc7 100644
--- a/generator/__main__.py
+++ b/generator/__main__.py
@@ -2,14 +2,14 @@ from __future__ import annotations
 
 import argparse
 import json
+import os
 import pathlib
+import platform
 import shutil
 import tempfile
 import time
 
-import modulus.filesystem
-
-import generator.arrange.generate
+import generator.audio_assets
 import generator.catalog
 import generator.engraving.cache
 import generator.engraving.fonts
@@ -17,12 +17,12 @@ import generator.engraving.pipeline
 import generator.engraving.types
 import generator.parts
 import generator.pico_artwork
-import generator.performance
 import generator.printing
+import generator.production
 import generator.score
+import generator.score_io
 import generator.summary
-import platform
-import os
+import modulus.filesystem
 
 RUNTIME_FONT_FILES = ("PetalumaScript.otf", "OFL.txt")
 
@@ -87,7 +87,7 @@ def generate_assets(args: argparse.Namespace) -> None:
     staged.mkdir(parents=True, exist_ok=True)
     copy_runtime_fonts(static_assets_dir, staged)
     report('generating performance parts')
-    performance_count = generator.arrange.generate.generate_performance_scores(data_dir / 'songs', staged / 'songs', composition_jobs=getattr(args, 'composition_jobs', 2), cache_dir=getattr(args, 'composition_cache', None), progress=progress, timings=timings)
+    performance_count = generator.production.generate_tree(data_dir / 'songs', staged / 'songs', jobs=getattr(args, 'composition_jobs', 2), cache_dir=getattr(args, 'composition_cache', None), progress=progress, timings=timings)
     if getattr(args, 'trace_level', 'summary') == 'summary':
       for path in (staged / 'analysis').glob('*.roles'):
         roles = json.loads(path.read_text())
@@ -95,13 +95,13 @@ def generate_assets(args: argparse.Namespace) -> None:
           trace = role.get('details', {}).get('selection_trace', {})
           trace.pop('decisions', None)
         path.write_text(json.dumps(roles, sort_keys=True, indent=2))
-    generator.score.validate_generated_tree(staged)
+    generator.score_io.validate_generated_tree(staged)
     if args.check:
       generator.summary.validate_expected_performance_summary(pathlib.Path(__file__).resolve().parents[1] / 'tests' / 'fixtures' / 'performance_summary.json', staged / 'songs')
     report('copying supplied recordings')
     song_ids = {generator.score.slugify(path.stem) for path in (data_dir / 'songs').glob('*.xml')}
-    audio_assets = generator.performance.copy_audio(static_assets_dir, staged, song_ids)
-    generator.performance.validate_recording_lengths(staged, audio_assets)
+    audio_assets = generator.audio_assets.copy_audio(static_assets_dir, staged, song_ids)
+    generator.audio_assets.validate_recording_lengths(staged, audio_assets)
     report('engraving pages')
     validated_pages = generator.engraving.pipeline.engrave_tree(staged, static_assets_dir / 'fonts' / 'petaluma', cache_dir=cache_dir, jobs=getattr(args, 'jobs', 1), progress=progress)
     report('generating printable parts')
@@ -109,7 +109,7 @@ def generate_assets(args: argparse.Namespace) -> None:
     report('rendering Pico titles')
     generator.pico_artwork.generate_titles(staged, static_assets_dir / 'fonts' / 'petaluma')
     report('validating score, page, and audio assets')
-    generator.score.validate_generated_tree(staged, validated_pages)
+    generator.score_io.validate_generated_tree(staged, validated_pages)
     report('building catalog database')
     generator.catalog.build_catalog(staged, audio_assets=audio_assets)
     with modulus.filesystem.publish_directories([(staged, output_dir)]):
diff --git a/generator/arrange/accompaniment.py b/generator/arrange/accompaniment.py
index b47e2ff..21bc2c4 100644
--- a/generator/arrange/accompaniment.py
+++ b/generator/arrange/accompaniment.py
@@ -1,20 +1,13 @@
 """One learned accompaniment per instrument, reused at authored form positions."""
 from __future__ import annotations
 
-import copy
 import fractions
 
 import generator.accompaniment
-import generator.acoustic
-import generator.acoustic_voicing
-import generator.electric
-import generator.guitar
-import generator.fretboard
-import generator.model
-import generator.parts
-import generator.score
 import generator.arrange.form
 import generator.arrange.pickup
+import generator.model
+import generator.score
 
 def harmonic_key(measure, previous):
 
diff --git a/generator/arrange/assembly.py b/generator/arrange/assembly.py
new file mode 100644
index 0000000..7c8c367
--- /dev/null
+++ b/generator/arrange/assembly.py
@@ -0,0 +1,100 @@
+"""Assemble source-defined role windows without composing or respelling."""
+from __future__ import annotations
+import copy
+import fractions
+
+import generator.accompaniment
+import generator.arrange.pickup
+import generator.composition_types
+import generator.fretboard
+import generator.model
+import generator.parts
+import generator.validation
+
+def mask(document, allowed):
+  """Apply source-defined role exclusions, without observing another part."""
+  absolute = fractions.Fraction()
+  for measure in document['staves'][0]['measures']:
+    length = generator.model.fraction(measure['duration'])
+    for voice in measure['voices']:
+      selected = []
+      for n in voice['notes']:
+        start = absolute + generator.model.fraction(n['onset'])
+        end = start + generator.model.fraction(n['duration'])
+        intervals = [(max(start, a), min(end, b)) for a, b in allowed if a < end and b > start]
+        for a, b in intervals:
+          note = copy.deepcopy(n)
+          if a != start:
+            note['onset'] = generator.model.rational(a - absolute)
+            for pitch in note['pitches']:
+              pitch.pop('tie_from', None)
+          generator.arrange.pickup.truncate(note, b - absolute)
+          if a < b:
+            selected.append(note)
+      voice['notes'] = fill(selected, length, measure['id'] + '_' + voice['id'], voice['id'])
+    absolute += length
+  staff = document['staves'][0]
+  staff['tuplets'] = generator.arrange.pickup.retain_links(staff['measures'], staff.get('tuplets', []))
+
+def fill(notes, length, prefix, voice='voice_arranged'):
+  notes = sorted(notes, key=lambda n: generator.model.fraction(n['onset']))
+  result = []
+  cursor = fractions.Fraction()
+
+  def rests(end):
+    nonlocal cursor
+    for duration, written in generator.accompaniment.written_durations(end - cursor):
+      result.append(generator.model.make_event(prefix + '_rest_' + str(len(result)), cursor, duration, 'rest', written=written) | {'voice': voice})
+      cursor += duration
+
+  for n in notes:
+    start = generator.model.fraction(n['onset'])
+    if start < cursor:
+      raise ValueError(prefix + ': overlapping independently generated roles')
+    rests(start)
+    n['voice'] = voice
+    result.append(n)
+    cursor = start + generator.model.fraction(n['duration'])
+  rests(length)
+  return result
+
+def assemble(source, results):
+  """Union prevalidated role windows; no selection or pitch/fingering rewrite."""
+  documents = {}
+  for part in generator.parts.PART_TYPES:
+    selected = [results[r]['document'] for r in generator.composition_types.ROLES if r.startswith(part + '_')]
+    document = copy.deepcopy(selected[0])
+    staff = document['staves'][0]
+    if part == 'vocal':
+      documents[part] = document
+      continue
+    staff['tuplets'] = []
+    staff['octave_shifts'] = []
+    staff['scale_spans'] = []
+    for other in selected:
+      for field in ('tuplets', 'octave_shifts', 'scale_spans'):
+        staff[field].extend(copy.deepcopy(other['staves'][0].get(field, [])))
+    for i, m in enumerate(staff['measures']):
+      # Tuplet rests belong to the source/role rhythm and must survive union.
+      lanes = {}
+      for d in selected:
+        for voice in d['staves'][0]['measures'][i]['voices']:
+          lane = voice['id'] if part == 'acoustic' and voice['id'] in ('upper', 'bass') else 'voice_arranged'
+          sounding = [copy.deepcopy(n) for n in voice['notes'] if n['pitches'] or n.get('tuplet_ids')]
+          if sounding:
+            lanes.setdefault(lane, []).extend(sounding)
+      lanes = lanes or {'voice_arranged': []}
+      m['voices'] = [{'id': lane, 'notes': fill(notes, generator.model.fraction(m['duration']), m['id'] + '_' + lane, lane)} for lane, notes in lanes.items()]
+      # Attribute changes belong to source melody pickups and are assembly metadata.
+      for d in selected:
+        other = d['staves'][0]['measures'][i]
+        if other.get('attributes'):
+          m['attributes'] = copy.deepcopy(other['attributes'])
+    staff['tuplets'] = generator.arrange.pickup.retain_links(staff['measures'], staff['tuplets'])
+    owners = {n['id']: v['id'] for m in staff['measures'] for v in m['voices'] for n in v['notes']}
+    for span in staff['tuplets']:
+      span['voice'] = owners[span['start']]
+    generator.validation.validate_document(document)
+    generator.fretboard.validate_document(document)
+    documents[part] = document
+  return documents
diff --git a/generator/arrange/ending.py b/generator/arrange/ending.py
index b24aa3e..4951379 100644
--- a/generator/arrange/ending.py
+++ b/generator/arrange/ending.py
@@ -4,44 +4,30 @@ import fractions
 
 import generator.accompaniment
 import generator.acoustic_voicing
+import generator.arrange.ending_plan
 import generator.comping
 import generator.fretboard
 import generator.model
 import generator.parts
 import generator.score
-
-BARS = 3
-
-def template(source):
-  result = copy.deepcopy(source[-1])
-  # An ending is three full bars in the final active meter, never a pickup.
-  for change in result.get('attributes', []):
-    for key in ('meter', 'key', 'clef', 'transpose', 'staff_details'):
-      if key in change:
-        result[key] = copy.deepcopy(change[key])
-  result.update(duration=generator.model.rational(generator.model.meter_length(result['meter'])), implicit=False,
-    attributes=[], harmonies=[], voices=[], tempos=[], section_label='')
-  result['time_signature'] = generator.model.meter_label(result['meter'])
-  return result
-
-def duration(source):
-  return BARS * generator.model.fraction(template(source)['duration']) if source else fractions.Fraction()
+import generator.vocabulary
 
 def chord(source):
   effective = [{**m, 'harmonies': [h for h in m['harmonies'] if not h.get('chord_optional')]} for m in source]
   prior = generator.accompaniment.carried_chords(effective)[-1]
   return generator.accompaniment.active_chord(effective[-1], generator.model.fraction(effective[-1]['duration']), prior)
 
-def append(source, output, part, *, sounding=False, center=55):
+def append(source, output, part, *, sounding=False, center=55, composition=None):
+  composition = composition or generator.vocabulary.current()
   if not source or not output:
     return
-  model = template(source)
+  model = generator.arrange.ending_plan.template(source)
   harmony = chord(source)
   grip = ()
   if sounding:
     if harmony is None:
       raise ValueError('Ending: final performed harmony is missing or N.C.; cannot invent a closing chord')
-    options = generator.comping.voicings(generator.comping.semantic_key(harmony), part)
+    options = generator.comping.voicings(generator.comping.semantic_key(harmony), part, composition=composition)
     recent = {}
     for m in reversed(output):
       for n in sorted(generator.score.measure_notes(m), key=lambda n: generator.model.fraction(n['onset']), reverse=True):
@@ -55,10 +41,10 @@ def append(source, output, part, *, sounding=False, center=55):
     if part == 'acoustic':
       bass = next((recent[s] for s in (5, 6) if s in recent), None)
       previous = generator.acoustic_voicing.Voicing(bass, *(recent[s] for s in (4, 3, 2))) if bass and all(s in recent for s in (4, 3, 2)) else ()
-    grip = min(options, key=lambda v: (generator.comping.local_cost(part, generator.comping.semantic_key(harmony), v, center).moved(generator.comping.movement(part, previous, v)), v))
+    grip = min(options, key=lambda v: (generator.comping.local_cost(part, generator.comping.semantic_key(harmony), v, center, composition=composition).moved(generator.comping.movement(part, previous, v)), v))
   length = generator.model.fraction(model['duration'])
   previous = None
-  for index in range(BARS):
+  for index in range(generator.arrange.ending_plan.BARS):
     measure = generator.parts.build_measure(model, f'measure_{len(output) + 1}', 'rest', part, None, 'Ending' if index == 0 else '')
     measure['ending_sustain'] = True
     if index == 0 and harmony:
@@ -77,4 +63,4 @@ def append(source, output, part, *, sounding=False, center=55):
         cursor += duration
       measure['voices'] = [{'id': 'voice_arranged', 'notes': notes}]
     output.append(measure)
-  generator.score.reidentify(output[-BARS:], [])
+  generator.score.reidentify(output[-generator.arrange.ending_plan.BARS:], [])
diff --git a/generator/arrange/ending_plan.py b/generator/arrange/ending_plan.py
new file mode 100644
index 0000000..6d40af7
--- /dev/null
+++ b/generator/arrange/ending_plan.py
@@ -0,0 +1,22 @@
+"""Source-derived ending geometry, independent of instrument composition."""
+import copy
+import fractions
+
+import generator.model
+
+BARS = 3
+
+def template(source):
+  result = copy.deepcopy(source[-1])
+  # An ending is three full bars in the final active meter, never a pickup.
+  for change in result.get('attributes', []):
+    for key in ('meter', 'key', 'clef', 'transpose', 'staff_details'):
+      if key in change:
+        result[key] = copy.deepcopy(change[key])
+  result.update(duration=generator.model.rational(generator.model.meter_length(result['meter'])), implicit=False,
+    attributes=[], harmonies=[], voices=[], tempos=[], section_label='')
+  result['time_signature'] = generator.model.meter_label(result['meter'])
+  return result
+
+def duration(source):
+  return BARS * generator.model.fraction(template(source)['duration']) if source else fractions.Fraction()
diff --git a/generator/arrange/form.py b/generator/arrange/form.py
index 0f34b13..743e219 100644
--- a/generator/arrange/form.py
+++ b/generator/arrange/form.py
@@ -1,8 +1,12 @@
 from __future__ import annotations
 
 import dataclasses
+import fractions
 import typing
 
+import generator.arrange.ending_plan
+import generator.arrange.pickup
+import generator.model
 import generator.score
 
 @dataclasses.dataclass(frozen=True)
@@ -55,3 +59,57 @@ def full_arrangement_sections(measures: list[dict], part_type: str) -> list[Arra
     for label, start, count, index in specs
     if count > 0
   ]
+
+@dataclasses.dataclass(frozen=True)
+class FormPlan:
+  sections: tuple[ArrangementSection, ...]
+  windows: tuple[tuple[fractions.Fraction, fractions.Fraction, str], ...]
+  stops: tuple[tuple[int, fractions.Fraction] | None, ...]
+  @classmethod
+  def read(cls, document, part):
+    source = generator.score.source_staff(document)['measures']
+    sections = tuple(full_arrangement_sections(source, part))
+    stops = tuple(section_stop(source, section, sections[i + 1] if i + 1 < len(sections) else None) for i, section in enumerate(sections))
+    return cls(sections, _windows(document, part, sections), stops)
+
+def section_stop(source, section, following):
+  if following is None or not generator.score.body_start_measure_index(source):
+    return None
+  last = section.source_measure_index + section.measure_count - 1
+  pad = generator.arrange.pickup.offset(source[last], source[0])
+  if following.role == 'slash':
+    return last, pad
+  if following.role == 'melody' and generator.arrange.pickup.enters(following, source):
+    attacks = [generator.model.fraction(note['onset']) for note in generator.score.measure_notes(source[0]) if note['pitches']]
+    if attacks:
+      return last, pad + min(attacks)
+  return None
+
+def windows(document, part):
+  return FormPlan.read(document, part).windows
+
+def _windows(document, part, sections):
+  source = generator.score.source_staff(document)['measures']
+  result, cursor = [], fractions.Fraction()
+  for section in sections:
+    duration = sum((generator.model.fraction(m['duration']) for m in source[section.source_measure_index:section.source_measure_index + section.measure_count]), fractions.Fraction())
+    role = {'slash': 'solo', 'vocal': 'melody'}.get(section.role, section.role)
+    if section.role in ('vocal', 'melody') and generator.arrange.pickup.enters(section, source) and result:
+      attacks = [generator.model.fraction(n['onset']) for n in generator.score.measure_notes(source[0]) if n['pitches']]
+      if attacks:
+        start = cursor - generator.model.fraction(source[0]['duration']) + min(attacks)
+        a, _, old = result[-1]
+        result[-1] = (a, start, old)
+        result.append((start, cursor, part + '_' + role))
+    end = cursor + duration
+    start = cursor
+    if section.role == 'slash' and generator.score.body_start_measure_index(source) and result:
+      # Allocate the source's complete pickup bar before composition. This
+      # does not inspect either generated solo; a role may leave it silent.
+      start = cursor - generator.model.fraction(source[0]['duration'])
+      a, _, old = result[-1]
+      result[-1] = (a, start, old)
+    result.append((start, end, part + '_' + role))
+    cursor = end
+  result.append((cursor, cursor + generator.arrange.ending_plan.duration(source), part + ('_accompaniment' if part != 'vocal' else '_rest')))
+  return tuple(result)
diff --git a/generator/arrange/generate.py b/generator/arrange/generate.py
index 80e82ef..cf3490e 100644
--- a/generator/arrange/generate.py
+++ b/generator/arrange/generate.py
@@ -2,36 +2,31 @@ from __future__ import annotations
 
 import copy
 import fractions
-import pathlib
 
 import generator.accompaniment
-import generator.arrange.accompaniment
 import generator.acoustic
 import generator.acoustic_voicing
 import generator.arrange.ending
 import generator.arrange.form
 import generator.arrange.pickup
+import generator.comping
 import generator.electric
 import generator.fretboard
 import generator.guitar
 import generator.melody
 import generator.model
-import generator.musicxml
 import generator.parts
 import generator.score
-import generator.solo.arrangement
-import generator.comping
 import generator.vocabulary
-import generator.production
 
 FINAL_SECTION_INDEX = 5
 
-def arrange_document(document: dict, part_type: str) -> dict:
+def arrange_document(document: dict, part_type: str, *, composition=None) -> dict:
   """Canonical source-only template; solos are inserted by production roles."""
+  composition = composition or generator.vocabulary.CompositionContext.create(generator.vocabulary.load(), part_type + '_accompaniment')
   document = generator.parts.prepare_document(document)
-  with generator.vocabulary.using(generator.vocabulary.load(), part_type + '_accompaniment'):
-    backing = generator.comping.Canonical(document, part_type, 'canonical') if part_type != 'vocal' else None
-    return _arrange_document(document, part_type, accompaniment=backing)
+  backing = generator.comping.Canonical(document, part_type, 'canonical', composition=composition) if part_type != 'vocal' else None
+  return _arrange_document(document, part_type, accompaniment=backing, composition=composition)
 
 def section_source(source: list[dict], section, next_section=None) -> list[dict]:
   result = copy.deepcopy(source)
@@ -44,12 +39,14 @@ def section_source(source: list[dict], section, next_section=None) -> list[dict]
     generator.arrange.pickup.harmonies(destination, result[0])
   return result
 
-def _arrange_document(document: dict, part_type: str, plans=None, *, owned=None, accompaniment=None) -> dict:
+def _arrange_document(document: dict, part_type: str, plan=None, *, owned=None, accompaniment=None, composition=None) -> dict:
+  composition = composition or generator.vocabulary.current()
   if part_type not in generator.parts.PART_TYPES:
     raise ValueError(f'unknown arrangement part: {part_type}')
   staff = generator.score.source_staff(document)
   source = staff['measures']
-  sections = generator.arrange.form.full_arrangement_sections(source, part_type)
+  plan = plan or generator.arrange.form.FormPlan.read(document, part_type)
+  sections = plan.sections
   output, tuplets, octave_shifts, voicing_origins = [], [], [], []
   absolute = fractions.Fraction()
   source_starts = []
@@ -62,16 +59,8 @@ def _arrange_document(document: dict, part_type: str, plans=None, *, owned=None,
     section_measures = section_source(source, section, sections[index + 1] if index + 1 < len(sections) else None)
     previous = generator.accompaniment.carried_chords(section_measures)
     segment = []
-    stop = None
+    stop = plan.stops[index]
     next_section = sections[index + 1] if index + 1 < len(sections) else None
-    if next_section and generator.score.body_start_measure_index(source):
-      last = section.source_measure_index + section.measure_count - 1
-      if next_section.role == 'slash':
-        stop = (last, generator.model.fraction(section_measures[last]['duration']) - generator.model.fraction(source[0]['duration']))
-      elif next_section.role == 'melody' and generator.arrange.pickup.enters(next_section, source):
-        attacks = [generator.model.fraction(n['onset']) for n in generator.score.measure_notes(source[0]) if n['pitches']]
-        if attacks:
-          stop = (last, generator.model.fraction(section_measures[last]['duration']) - generator.model.fraction(source[0]['duration']) + min(attacks))
     for si in range(section.source_measure_index, section.source_measure_index + section.measure_count):
       m = section_measures[si]
       if role == 'accompaniment' and accompaniment is not None:
@@ -111,7 +100,7 @@ def _arrange_document(document: dict, part_type: str, plans=None, *, owned=None,
   if sections and sections[-1].section_index == FINAL_SECTION_INDEX:
     generator.arrange.ending.append(source, output, part_type,
       sounding=part_type != 'vocal' and (owned is None or 'accompaniment' in owned),
-      center=generator.vocabulary.role(part_type + '_accompaniment').get('center', 55))
+      center=composition.role(part_type + '_accompaniment').get('center', 55), composition=composition)
   tuplets = generator.arrange.pickup.retain_links(output, tuplets)
   result = generator.score.make_arranged_document(document, staff, staff_id='staff_arranged_' + part_type, staff_name=part_type.capitalize(), role='vocal' if part_type == 'vocal' else 'guitar', arrangement_part_type=part_type, measures=output, tuplets=tuplets, octave_shifts=octave_shifts)
   result['metadata'].setdefault('tempo', 124)
@@ -123,15 +112,12 @@ def _arrange_document(document: dict, part_type: str, plans=None, *, owned=None,
     generator.acoustic.combine(result)
   elif part_type == 'electric' and (owned is None or 'melody' in owned):
     generator.melody.harmonize(result)
-    generator.guitar.place_guitar(result)
+    generator.guitar.place_guitar(result, composition=composition)
     if generator.accompaniment.connect_continuations(result):
-      generator.guitar.place_guitar(result)
+      generator.guitar.place_guitar(result, composition=composition)
   # Source labels identify the head while arranging; published labels identify
   # the complete performance, including its lead-in and repeated choruses.
   for number, measure in enumerate(output, 1):
     measure['number'] = str(number)
   generator.fretboard.validate_document(result)
   return result
-
-def generate_performance_scores(source_dir: pathlib.Path, output_dir: pathlib.Path, *, composition_jobs=2, cache_dir=None, progress=False, timings=None) -> int:
-  return generator.production.generate_tree(source_dir, output_dir, jobs=composition_jobs, cache_dir=cache_dir, progress=progress, timings=timings)
diff --git a/generator/audio_assets.py b/generator/audio_assets.py
new file mode 100644
index 0000000..cac441f
--- /dev/null
+++ b/generator/audio_assets.py
@@ -0,0 +1,68 @@
+"""Validate and copy supplied recordings without synthesis or transformation."""
+from __future__ import annotations
+
+import fractions
+import hashlib
+import json
+import re
+import shutil
+import wave
+
+import generator.model
+import generator.performance
+
+TEMPOS = tuple(range(60, 121, 10))
+
+def describe_wav(path, root, *, song_id='', bpm=0):
+  if path.is_symlink() or not path.is_file() or not path.resolve().is_relative_to(root.resolve()):
+    raise ValueError(f'{path}: expected a contained regular WAV')
+  try:
+    with wave.open(str(path), 'rb') as audio:
+      channels, rate, frames = audio.getnchannels(), audio.getframerate(), audio.getnframes()
+      if audio.getcomptype() != 'NONE' or audio.getsampwidth() != 2 or channels not in (1, 2) or not 8000 <= rate <= 192000 or frames <= 0:
+        raise ValueError('expected nonempty mono/stereo PCM16 WAV')
+      remaining = frames
+      while remaining:
+        count = min(remaining, 65536)
+        if len(audio.readframes(count)) != count * channels * 2:
+          raise ValueError('truncated WAV data')
+        remaining -= count
+  except (wave.Error, EOFError) as error:
+    raise ValueError(f'{path}: invalid WAV: {error}') from error
+  with path.open('rb') as source:
+    digest = hashlib.file_digest(source, 'sha256').hexdigest()
+  return dict(path=path.relative_to(root).as_posix(), sha256=digest, channels=channels, sample_rate=rate, frames=frames, song_id=song_id, bpm=bpm)
+
+def copy_audio(static, destination, song_ids):
+  entries = []
+  inputs = [(static / 'sounds' / name, '', 0) for name in ('beat1.wav', 'beat2.wav')]
+  for path in sorted((static / 'backing').glob('*.wav')):
+    match = re.fullmatch(r'([a-z0-9]+(?:_[a-z0-9]+)*)_(60|70|80|90|100|110|120)\.wav', path.name)
+    if not match:
+      raise ValueError(f'{path}: unsupported backing filename or tempo')
+    if match[1] not in song_ids:
+      continue
+    inputs.append((path, match[1], int(match[2])))
+  for source, song_id, bpm in inputs:
+    description = describe_wav(source, static, song_id=song_id, bpm=bpm)
+    target = destination / description['path']
+    target.parent.mkdir(parents=True, exist_ok=True)
+    shutil.copyfile(source, target)
+    entries.append(description)
+  return entries
+
+def validate_recording_lengths(root, entries):
+  durations = {}
+  for path in sorted((root / 'songs').glob('*.json')):
+    document = json.loads(path.read_text())
+    performance = generator.performance.timing(document)
+    song_id = performance['song_id']
+    duration = generator.model.fraction(performance['duration']) + performance['count_in_beats']
+    if song_id in durations and durations[song_id] != duration:
+      raise ValueError(f'{song_id}: parts disagree about performance duration')
+    durations[song_id] = duration
+  for entry in entries:
+    if entry['song_id']:
+      seconds = fractions.Fraction(entry['frames'], entry['sample_rate'])
+      if seconds < durations[entry['song_id']] * 60 / entry['bpm']:
+        raise ValueError(f"{entry['path']}: backing recording is shorter than count-in and score")
diff --git a/generator/cache.py b/generator/cache.py
new file mode 100644
index 0000000..3e0f5a2
--- /dev/null
+++ b/generator/cache.py
@@ -0,0 +1,82 @@
+"""Content identities and atomic storage shared by generator cache adapters."""
+from __future__ import annotations
+import ast
+import contextlib
+import functools
+import hashlib
+import json
+import os
+import pathlib
+import shutil
+import tempfile
+
+ROOT = pathlib.Path(__file__).resolve().parent
+
+@functools.lru_cache(maxsize=256)
+def imports(content):
+  modules = set()
+  for node in ast.walk(ast.parse(content)):
+    if isinstance(node, ast.Import):
+      modules.update(alias.name for alias in node.names if alias.name.startswith('generator.'))
+    elif isinstance(node, ast.ImportFrom) and node.module and node.module.startswith('generator'):
+      modules.add(node.module)
+      modules.update(node.module + '.' + alias.name for alias in node.names)
+  return tuple(sorted(modules))
+
+def source_identity(entrypoints):
+  """Conservatively include the transitive imports of explicit stage roots.
+
+  Read bytes on every call, so edits in a long-lived build process invalidate
+  both code content and newly introduced dependencies. Only parsing is cached.
+  """
+  pending, sources = list(entrypoints), {}
+  while pending:
+    module = pending.pop()
+    relative = module.split('.')[1:]
+    path = ROOT.joinpath(*relative).with_suffix('.py') if relative else ROOT / '__init__.py'
+    if not path.is_file():
+      path = ROOT.joinpath(*relative, '__init__.py')
+    if path in sources or not path.is_file():
+      continue
+    content = path.read_bytes()
+    sources[path] = hashlib.sha256(content).hexdigest()
+    pending.extend(imports(content))
+    pending.extend('.'.join(module.split('.')[:i]) for i in range(1, len(module.split('.'))))
+  return {path.relative_to(ROOT).as_posix(): sources[path] for path in sorted(sources)}
+
+def fingerprint(value):
+  return hashlib.sha256(json.dumps(value, sort_keys=True, separators=(',', ':')).encode()).hexdigest()
+
+def write_json(path, value):
+  path.parent.mkdir(parents=True, exist_ok=True)
+  temporary = None
+  try:
+    with tempfile.NamedTemporaryFile('w', dir=path.parent, delete=False) as output:
+      temporary = pathlib.Path(output.name)
+      json.dump(value, output, sort_keys=True)
+    os.replace(temporary, path)
+  finally:
+    if temporary is not None:
+      temporary.unlink(missing_ok=True)
+
+def has_symlink(path):
+  return any(parent.is_symlink() for parent in (path, *path.parents))
+
+@contextlib.contextmanager
+def stage_entry(entry, prefix):
+  if has_symlink(entry.parent):
+    raise ValueError('cache directories must not be symlinks')
+  entry.parent.mkdir(parents=True, exist_ok=True)
+  if entry.is_symlink() or entry.is_file():
+    entry.unlink(missing_ok=True)
+  entry.mkdir(exist_ok=True)
+  with tempfile.TemporaryDirectory(prefix=prefix, dir=entry.parent) as temporary:
+    yield pathlib.Path(temporary)
+
+def publish_files(entry, staged, names):
+  """Publish complete files in order, with the artifact manifest last."""
+  for name in names:
+    target = entry / name
+    if target.is_dir() and not target.is_symlink():
+      shutil.rmtree(target)
+    (staged / name).replace(target)
diff --git a/generator/catalog.py b/generator/catalog.py
index 29990b6..96d4c33 100644
--- a/generator/catalog.py
+++ b/generator/catalog.py
@@ -10,7 +10,7 @@ import sys
 if __name__ == '__main__' and __package__ is None:
   sys.path.insert(0, str(pathlib.Path(__file__).resolve().parents[1]))
 
-import generator.performance
+import generator.audio_assets
 
 APPLICATION_ID = 0x56414D50
 SONG_COLUMNS = """
@@ -58,12 +58,12 @@ def populate(connection: sqlite3.Connection, root: pathlib.Path, audio_assets=No
     for path in sorted(root.glob('sounds/*.wav')):
       if path.name not in ('beat1.wav', 'beat2.wav'):
         raise ValueError(f'{path}: unknown metronome sample')
-      audio_assets.append(generator.performance.describe_wav(path, root))
+      audio_assets.append(generator.audio_assets.describe_wav(path, root))
     for path in sorted(root.glob('backing/*.wav')):
       match = re.fullmatch(r'([a-z0-9]+(?:_[a-z0-9]+)*)_(60|70|80|90|100|110|120)\.wav', path.name)
       if not match:
         raise ValueError(f'{path}: invalid backing filename')
-      audio_assets.append(generator.performance.describe_wav(path, root, song_id=match[1], bpm=int(match[2])))
+      audio_assets.append(generator.audio_assets.describe_wav(path, root, song_id=match[1], bpm=int(match[2])))
   folder = root / 'songs'
   if (folder.exists() or folder.is_symlink()) and not folder.is_dir():
     raise ValueError(f'{folder}: score asset directory not found')
diff --git a/generator/chord_families.py b/generator/chord_families.py
index 7368aaa..61ffc14 100644
--- a/generator/chord_families.py
+++ b/generator/chord_families.py
@@ -1,10 +1,11 @@
 """Transposable guitar families, derived from the written chord and legal grips."""
-import generator.harmony
 import generator.fretboard
+import generator.harmony
 import generator.model
 import generator.vocabulary
 
-def acoustic(chord, grip):
+def acoustic(chord, grip, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   degrees = generator.harmony.degrees(chord)
   root = int(generator.model.NATURAL[chord['root']['letter']] + generator.model.alteration(chord['root']['alter']))
   classes = {d: (root + generator.harmony.degree_semitones(d, a)) % 12 for d, a in degrees.items()}
@@ -14,7 +15,7 @@ def acoustic(chord, grip):
   kind = 'extended' if terminal and color else 'tetrad' if terminal else 'triad'
   bass = next((d for d in (1, 5, 3) if classes.get(d) == grip[0].midi % 12), None)
   slots = {'root': 1, 'fifth': 5, 'guide': guide, 'terminal': terminal, 'color': color}
-  policy = generator.vocabulary.accompaniment('acoustic')['voicing_families']
+  policy = composition.accompaniment('acoustic')['voicing_families']
   orders = policy[kind].get(f'{grip[0].string_number}/{bass}', ())
   upper = tuple(p.midi % 12 for p in grip[1:])
   preferred = any(all(slots[s] in classes for s in order) and tuple(classes[slots[s]] for s in order) == upper for order in orders)
@@ -37,10 +38,11 @@ def electric(grip):
       return 'drop-two'
   return 'close-position' if pitches and pitches[-1] - pitches[0] < 12 else 'compact-open'
 
-def coverage(chord, options, part):
+def coverage(chord, options, part, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   if part == 'electric':
-    return {name: sum(electric(v) == name for v in options) for name in generator.vocabulary.accompaniment('electric')['voicing_families']['rank']}
-  families = [acoustic(chord, v) for v in options]
+    return {name: sum(electric(v) == name for v in options) for name in composition.accompaniment('electric')['voicing_families']['rank']}
+  families = [acoustic(chord, v, composition=composition) for v in options]
   result = []
   for string in (5, 6):
     for degree in (1, 5):
diff --git a/generator/comping.py b/generator/comping.py
index 6da5eeb..ef271bd 100644
--- a/generator/comping.py
+++ b/generator/comping.py
@@ -2,26 +2,25 @@
 from __future__ import annotations
 import copy
 import dataclasses
+import fractions
 import functools
 import json
-import fractions
 import typing
 
 import generator.accompaniment
 import generator.acoustic
-import generator.comping_rhythm
-import generator.chord_families
 import generator.acoustic_voicing
 import generator.arrange.form
-import generator.arrange.pickup
+import generator.chord_families
+import generator.comping_rhythm
 import generator.fretboard
 import generator.guitar
 import generator.harmony
 import generator.model
 import generator.parts
 import generator.score
-import generator.vocabulary
 import generator.solo.policy
+import generator.vocabulary
 
 def semantic_key(chord):
   return json.dumps({k: chord[k] for k in ('root', 'kind', 'degrees', 'bass', 'inversion') if k in chord}, sort_keys=True)
@@ -38,12 +37,15 @@ def requirements(chord, part):
     raise ValueError('acoustic accompaniment requires a written bass, root or fifth')
   return dataclasses.replace(result, basses=basses)
 
+def voicings(key, part, *, composition=None):
+  return _voicings(key, part, composition or generator.vocabulary.current())
+
 @functools.lru_cache(maxsize=2048)
-def voicings(key, part):
+def _voicings(key, part, composition):
   chord = json.loads(key)
   required = requirements(chord, part)
   if part == 'electric':
-    options = generator.guitar.chord_positions(required, prune=False, profile='electric')
+    options = generator.guitar.chord_positions(required, prune=False, profile='electric', composition=composition)
   elif part == 'acoustic':
     degrees = generator.harmony.degrees(chord)
     plain = degrees in ({1: 0, 3: 0, 5: 0}, {1: 0, 3: -1, 5: 0})
@@ -77,19 +79,21 @@ class VoicingCost(typing.NamedTuple):
   def moved(self, distance):
     return self._replace(effort=self.effort + distance)
 
-def voicing_preferences(part, grip, center):
-  return generator.guitar.voicing_preferences(grip, generator.guitar.voicing_preference(part + '_accompaniment', center))
+def voicing_preferences(part, grip, center, *, composition=None):
+  composition = composition or generator.vocabulary.current()
+  return generator.guitar.voicing_preferences(grip, generator.guitar.voicing_preference(part + '_accompaniment', center, composition=composition))
 
-def local_cost(part, key, grip, center):
+def local_cost(part, key, grip, center, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   required = requirements(json.loads(key), part)
   register = abs(fractions.Fraction(sum(p.midi for p in grip), len(grip)) - center)
-  preference = sum(voicing_preferences(part, grip, center))
+  preference = sum(voicing_preferences(part, grip, center, composition=composition))
   if part == 'electric':
-    value = generator.guitar.voicing_cost(grip, 'electric', required.allowed)
+    value = generator.guitar.voicing_cost(grip, 'electric', required.allowed, composition=composition)
     return VoicingCost(value.extended_grips, 3 * value.string_shortfall + value.family_penalty, value.effort + preference, value.missing_tones, register)
   # Familiar degree orders on either bass string, then balanced whole-form
   # movement, sounding register and hand position. Neither is an absolute ban.
-  family = generator.chord_families.acoustic(json.loads(key), grip)
+  family = generator.chord_families.acoustic(json.loads(key), grip, composition=composition)
   return VoicingCost(generator.fretboard.span_penalty(grip), int(not family['preferred']), preference, len(set(required.allowed) - {p.midi % 12 for p in grip}), register)
 
 def select_grips(layers, costs, part, seed, *, left=(), right=(), close=False):
@@ -184,9 +188,10 @@ def split_measures(flat, inputs, part):
   return tuple(output)
 
 class Canonical:
-  def __init__(self, document, part, seed):
+  def __init__(self, document, part, seed, *, composition=None, plan=None):
+    self.composition = composition or generator.vocabulary.current()
     self.part, self.seed = part, seed
-    self.policy = generator.vocabulary.role(part + '_accompaniment')
+    self.policy = self.composition.role(part + '_accompaniment')
     self.cache, self._reports, self._rhythm_reports = {}, {}, {}
     self.measures = generator.score.source_staff(document)['measures']
     # A held accompaniment chord may continue into the bar containing the
@@ -194,7 +199,8 @@ class Canonical:
     self.voice_id = self.measures[0]['voices'][0]['id']
     self.melody = generator.comping_rhythm.melody_contexts(document)
     self.first = generator.score.body_start_measure_index(self.measures)
-    sections = generator.arrange.form.full_arrangement_sections(self.measures, part)
+    plan = plan or generator.arrange.form.FormPlan.read(document, part)
+    sections = plan.sections
     self.closed = any(a.role == b.role == 'accompaniment' and a.source_measure_index + a.measure_count == len(self.measures)
       and b.source_measure_index == self.first for a, b in zip(sections, sections[1:]))
     carried = generator.accompaniment.carried_chords(self.measures)
@@ -204,7 +210,7 @@ class Canonical:
       size = 1
       if index + 1 < len(self.measures):
         lengths = [generator.model.fraction(m['duration']) for m in self.measures[index:index + 2]]
-        if self.measures[index]['time_signature'] == self.measures[index + 1]['time_signature'] and any(tuple(map(fractions.Fraction, p['lengths'])) == tuple(lengths) for p in generator.vocabulary.accompaniment(part)['patterns']):
+        if self.measures[index]['time_signature'] == self.measures[index + 1]['time_signature'] and any(tuple(map(fractions.Fraction, p['lengths'])) == tuple(lengths) for p in self.composition.accompaniment(part)['patterns']):
           size = 2
       self.groups.append(tuple((self.measures[i], carried[i], i) for i in range(index, index + size)))
       index += size
@@ -214,19 +220,9 @@ class Canonical:
     for section in sections:
       if section.role == 'accompaniment':
         self.pair_breaks.update((section.source_measure_index, section.source_measure_index + section.measure_count))
-    for section, following in zip(sections, sections[1:]):
-      if section.role != 'accompaniment' or not self.first:
-        continue
-      last = section.source_measure_index + section.measure_count - 1
-      pad = generator.arrange.pickup.offset(self.measures[last], self.measures[0])
-      if following.role == 'slash':
-        self.pair_stops.append((last, pad))
-      elif following.role == 'melody' and generator.arrange.pickup.enters(following, self.measures):
-        attacks = [generator.model.fraction(n['onset']) for n in generator.score.measure_notes(self.measures[0]) if n['pitches']]
-        if attacks:
-          self.pair_stops.append((last, pad + min(attacks)))
+    self.pair_stops = [stop for section, stop in zip(sections, plan.stops) if section.role == 'accompaniment' and stop is not None]
     breaks = [(i, fractions.Fraction()) for i in self.pair_breaks] + self.pair_stops
-    choices, locations, self.groove_report = generator.comping_rhythm.choose_cycles(self.groups, part, self.melody, seed, breaks=breaks)
+    choices, locations, self.groove_report = generator.comping_rhythm.choose_cycles(self.groups, part, self.melody, seed, breaks=breaks, composition=self.composition)
     self.patterns = {g[0][2]: (p, a) for g, (p, a, _) in zip(self.groups, choices)}
     self.locations = {g[0][2]: location for g, location in zip(self.groups, locations)}
     selected = [r for _, _, r in choices]
@@ -266,7 +262,7 @@ class Canonical:
       melody.extend((a + cursor, b + cursor) for a, b in self.melody[i])
       lengths.append(generator.model.fraction(m['duration']))
       cursor += lengths[-1]
-    return generator.comping_rhythm.candidates(flat, None, self.part, tuple(melody), self.seed + '/' + str(inputs[0][2]), lengths=tuple(lengths), limit=limit)
+    return generator.comping_rhythm.candidates(flat, None, self.part, tuple(melody), self.seed + '/' + str(inputs[0][2]), lengths=tuple(lengths), limit=limit, composition=self.composition)
   def acoustic_realizations(self, sources, bounds=None, stop=None):
     """Assign the canonical attack stream once, before splitting it into blocks.
 
@@ -313,14 +309,14 @@ class Canonical:
       offset, index = next((a, i) for a, i in reversed(offsets) if a <= start)
       events = tuple(e for e in rhythm.events if start <= (e.harmonic_time if e.harmonic_time is not None else e.start) < end)
       try:
-        options = voicings(semantic_key(chord), self.part)
+        options = voicings(semantic_key(chord), self.part, composition=self.composition)
       except ValueError as error:
         raise ValueError(f'source measure {inputs[index - inputs[0][2]][0]["number"]}, beat {start - offset + 1}: {error}') from error
       spans.append(HarmonyChoice(index, start, end, chord, events, dict(rhythm.families), options))
     return tuple(spans)
   def select(self, spans, *, left=(), right=(), close=False):
     layers = tuple(s.options for s in spans)
-    costs = tuple({v: local_cost(self.part, semantic_key(s.chord), v, self.policy.get('center', 55)) for v in layer} for s, layer in zip(spans, layers))
+    costs = tuple({v: local_cost(self.part, semantic_key(s.chord), v, self.policy.get('center', 55), composition=self.composition) for v in layer} for s, layer in zip(spans, layers))
     return select_grips(layers, costs, self.part, self.seed, left=left, right=right, close=close)
   def __call__(self, source, prior, index, *, sources=None, bounds=None, stop=None):
     group = next((g for g in self.groups if any(i == index for _, _, i in g)), ((source, prior, index),))
@@ -397,8 +393,8 @@ class Canonical:
       root = int(generator.model.NATURAL[span.chord['root']['letter']] + generator.model.alteration(span.chord['root']['alter']))
       rows.append({'source_index': span.index, 'onset': str(span.start), 'chord': generator.harmony.symbol(span.chord),
         'figure': span.figure, 'pattern_id': rhythm.pattern_id, 'tones': len(grip), 'bass': bool(bass), 'variant': variant,
-        'family': (generator.chord_families.acoustic(span.chord, grip) if self.part == 'acoustic' else generator.chord_families.electric(grip)) if grip else None,
-        'family_coverage': generator.chord_families.coverage(span.chord, span.options, self.part),
+        'family': (generator.chord_families.acoustic(span.chord, grip, composition=self.composition) if self.part == 'acoustic' else generator.chord_families.electric(grip)) if grip else None,
+        'family_coverage': generator.chord_families.coverage(span.chord, span.options, self.part, composition=self.composition),
         'fret_span': generator.fretboard.fret_span(grip),
         'span_group': ('fallback' if generator.fretboard.span_penalty(grip) else 'primary') if grip else None,
         'span_candidates': generator.chord_families.span_coverage(span.options),
@@ -407,9 +403,9 @@ class Canonical:
         'bass_string': bass.string_number if bass else None,
         'movement': movement(self.part, previous, grip), 'voicing_candidates': len(span.options)})
       if grip:
-        register, position = voicing_preferences(self.part, grip, self.policy.get('center', 55))
+        register, position = voicing_preferences(self.part, grip, self.policy.get('center', 55), composition=self.composition)
         travel = movement(self.part, previous, grip)
-        effort = generator.guitar.voicing_cost(grip, 'electric').effort if self.part == 'electric' else 0
+        effort = generator.guitar.voicing_cost(grip, 'electric', composition=self.composition).effort if self.part == 'electric' else 0
         rows[-1]['voicing_cost'] = {'movement': travel, 'grip_effort': str(effort), 'register': str(register), 'position': str(position), 'combined': str(travel + effort + register + position)}
       for event in span.events:
         lanes = ['bass', 'upper'] if event.lane == 'combined' else [event.lane]
diff --git a/generator/comping_rhythm.py b/generator/comping_rhythm.py
index dcf26c9..5ceb6dd 100644
--- a/generator/comping_rhythm.py
+++ b/generator/comping_rhythm.py
@@ -5,8 +5,8 @@ import itertools
 
 import generator.accompaniment
 import generator.model
-import generator.solo.analysis
 import generator.solo.policy
+import generator.source
 import generator.vocabulary
 
 def meter_context(measure):
@@ -90,7 +90,7 @@ class Rhythm:
     return tuple((e.lane, str(e.start), str(e.end - e.start), str(e.harmonic_time)) for e in self.events)
 
 def melody_contexts(document):
-  melody = generator.solo.analysis.attacks(document)
+  melody = generator.source.attacks(document)
   result, cursor = [], fractions.Fraction()
   for m in document['staves'][0]['measures']:
     length = generator.model.fraction(m['duration'])
@@ -247,9 +247,10 @@ def evaluate(events, part, melody, harmony, lengths):
   divisor = max(1, len(lengths))
   return tuple((k, v / divisor) for k, v in (('activity', activity), ('melody_support', support), ('harmonic_support', coverage), ('articulation', articulation)))
 
-def candidates(measure, prior, part, melody, seed, *, lengths=None, limit=None, grouping=()):
+def candidates(measure, prior, part, melody, seed, *, lengths=None, limit=None, grouping=(), composition=None):
+  composition = composition or generator.vocabulary.current()
   lengths = lengths or (generator.model.fraction(measure['duration']),)
-  policy = generator.vocabulary.accompaniment(part)
+  policy = composition.accompaniment(part)
   result = []
   for pattern in patterns_for(policy, measure, lengths, grouping):
     for anticipate in (False, True):
@@ -371,13 +372,14 @@ def realize_acoustic_form(rhythms, context):
 def form_cost(rhythms, groups):
   return sum(r.cost * len(g) for r, g in zip(rhythms, groups))
 
-def choose_cycles(groups, part, melody, seed, *, breaks=()):
+def choose_cycles(groups, part, melody, seed, *, breaks=(), composition=None):
   """Select a small recurring vocabulary against every occurrence in the form.
 
   No local shortlist precedes whole-form evaluation. A pattern/mode is retained
   as one decision even where a chord boundary changes its legal release.
   """
-  policy = generator.vocabulary.accompaniment(part)
+  composition = composition or generator.vocabulary.current()
+  policy = composition.accompaniment(part)
   settings = policy['groove']
   selected, locations, reports = [], [], []
   runs = []
@@ -463,7 +465,7 @@ def choose_cycles(groups, part, melody, seed, *, breaks=()):
       selected.append((p, anticipate, cache[i, p['id'], anticipate]))
       locations.append({'cycle_start': run[0][0][2], 'cycle_slot': i % len(cycle), 'base_pattern': p['id'], 'fill': None})
   context = acoustic_context(groups, melody, breaks) if part == 'acoustic' else None
-  add_fills(groups, selected, locations, part, melody, seed, context=context)
+  add_fills(groups, selected, locations, part, melody, seed, context=context, composition=composition)
   if context:
     realized = realize_acoustic_form([r for _, _, r in selected], context)
     selected = [(p, a, r) for (p, a, _), r in zip(selected, realized)]
@@ -472,9 +474,10 @@ def choose_cycles(groups, part, melody, seed, *, breaks=()):
       report['attack_assignment'] = 'sequential_combined_except_eighth_pairs'
   return selected, locations, reports
 
-def add_fills(groups, selected, locations, part, melody, seed, *, context=None):
+def add_fills(groups, selected, locations, part, melody, seed, *, context=None, composition=None):
   """Fixed source-position answers; no iteration seed or generated lead input."""
-  policy = generator.vocabulary.accompaniment(part)
+  composition = composition or generator.vocabulary.current()
+  policy = composition.accompaniment(part)
   spacing = policy['groove']['fill_spacing_measures']
   if not groups:
     return
@@ -519,7 +522,7 @@ def add_fills(groups, selected, locations, part, melody, seed, *, context=None):
     if any(e.start < middle < e.end for e in current.events):
       continue
     for variation in policy['patterns']:
-      if variation['family'] != base['family'] or variation['lengths'] != base['lengths'] or variation.get('meter') != base.get('meter') or variation.get('grouping') != base.get('grouping'):
+      if variation['family'] != base['family'] or tuple(variation['lengths']) != tuple(base['lengths']) or variation.get('meter') != base.get('meter') or tuple(variation.get('grouping', ())) != tuple(base.get('grouping', ())):
         continue
       hybrid = {**base, 'id': base['id'] + '.fill.' + variation['id'], 'events':
         [r for r in base['events'] if fractions.Fraction(r['onset']) < middle] +
diff --git a/generator/compose.py b/generator/compose.py
index 2363e57..ba6197b 100644
--- a/generator/compose.py
+++ b/generator/compose.py
@@ -1,24 +1,27 @@
 """Explicit single-role build. Does not publish or consume an existing ensemble."""
 import argparse
 import json
-import time
 import pathlib
+import time
+
+import generator.composition
+import generator.composition_types
 import generator.musicxml
 import generator.parts
-import generator.production
+import generator.source
 
 def main():
   parser = argparse.ArgumentParser(description=__doc__)
   parser.add_argument('--song', type=pathlib.Path, required=True)
-  parser.add_argument('--role', choices=generator.production.ROLES, required=True)
+  parser.add_argument('--role', choices=generator.composition_types.ROLES, required=True)
   parser.add_argument('--data-dir', type=pathlib.Path, default=pathlib.Path('data'))
   parser.add_argument('--output', type=pathlib.Path, required=True)
   parser.add_argument('--cache-dir', type=pathlib.Path)
   parser.add_argument('--settings', type=pathlib.Path)
   args = parser.parse_args()
-  source = generator.production.SourceAnalysis.read(generator.parts.prepare_document(generator.musicxml.load_musicxml(args.song)))
+  source = generator.source.SourceAnalysis.read(generator.parts.prepare_document(generator.musicxml.load_musicxml(args.song)))
   start = time.monotonic()
-  result = generator.production.generate_role(source, args.role, args.data_dir, json.loads(args.settings.read_text()) if args.settings else {}, args.cache_dir)
+  result = generator.composition.generate_role(source, args.role, args.data_dir, json.loads(args.settings.read_text()) if args.settings else {}, args.cache_dir)
   args.output.parent.mkdir(parents=True, exist_ok=True)
   args.output.write_text(json.dumps(result, indent=2))
   print(f'{args.role}: {time.monotonic() - start:.2f}s wall; cached={result["cache_hit"]}; role generation/cache lookup {result["seconds"]:.2f}s')
diff --git a/generator/composition.py b/generator/composition.py
new file mode 100644
index 0000000..b1a2fa0
--- /dev/null
+++ b/generator/composition.py
@@ -0,0 +1,158 @@
+"""Independent, reproducible role generation from source and policy inputs.
+
+Only source documents and production resources enter generate_role. Completed
+roles and published assets are downstream values, never composition inputs.
+"""
+from __future__ import annotations
+import copy
+import dataclasses
+import functools
+import hashlib
+import json
+import pathlib
+import time
+
+import generator.accompaniment
+import generator.acoustic
+import generator.arrange.assembly
+import generator.arrange.form
+import generator.arrange.generate
+import generator.comping
+import generator.comping_rhythm
+import generator.composition_types
+import generator.fretboard
+import generator.input_audit
+import generator.role_cache
+import generator.score
+import generator.solo.arrangement
+import generator.solo.authored
+import generator.solo.composer
+import generator.solo.learned
+import generator.solo.notation
+import generator.solo.report
+import generator.source
+import generator.validation
+import generator.vocabulary
+
+VERSION = 'independent-roles-1'
+
+def dependencies(role, resources, measures=None):
+  names = ['harmony', 'lead_ins'] if role.endswith('_solo') else []
+  accompaniment = {}
+  if role.endswith('_accompaniment'):
+    policy = generator.vocabulary.accompaniment(role.split('_')[0], resources)
+    accompaniment = {'accompaniment': generator.comping_rhythm.relevant_policy(policy, measures) if measures is not None else policy}
+  return {'roles': {'role': resources['roles']['roles'][role], 'difficulty': resources['roles']['difficulty']},
+    **({'voicing_families': generator.vocabulary.accompaniment('electric', resources)['voicing_families']} if role == 'electric_melody' else {}),
+    **accompaniment,
+    **{name: resources[name] for name in names}}
+
+def _resource_key(directory, role):
+  return {'model': hashlib.sha256((directory / 'models' / 'solo.json').read_bytes()).hexdigest()} if role.endswith('_solo') else {}
+
+@functools.lru_cache(maxsize=4)
+def _solo_model(directory, fingerprint):
+  return generator.solo.learned.Model.load(pathlib.Path(directory) / 'models' / 'solo.json')
+
+def generate_role(source, role, data_dir, settings=None, cache_dir=None) -> generator.composition_types.RoleResult:
+  started = time.monotonic()
+  with generator.input_audit.composition(data_dir, role, cache_dir) as reads:
+    result = _generate_role(source, role, data_dir, settings, cache_dir)
+  # Observed reads are diagnostics, never cache identity or musical seeds.
+  result['trace'] = {**result['trace'], 'input_boundary': 'production data (including explicit authored repertoire), generator code, Python runtime, own role cache'}
+  result['observed_reads'] = sorted(reads)
+  result['seconds'] = time.monotonic() - started
+  return result
+
+def _generate_role(source, role, data_dir, settings=None, cache_dir=None):
+  if role not in generator.composition_types.ROLES:
+    raise ValueError('Unknown generation role: ' + role)
+  data_dir = pathlib.Path(data_dir)
+  resources = generator.vocabulary.load(data_dir / 'composition')
+  settings = settings or {}
+  registered = generator.solo.authored.lookup(source, role.removesuffix('_solo'), data_dir) if role.endswith('_solo') and not settings.get('predict', False) else None
+  algorithm = VERSION + '/' + generator.solo.learned.VERSION if role.endswith('_solo') else VERSION
+  inputs = {'version': algorithm, 'source': source.musical_key, 'role': role, 'settings': settings,
+    'vocabulary': dependencies(role, resources, generator.score.source_staff(source.document())['measures']), 'catalogs': ({'authored': registered['sha256'], 'id': registered['id'], 'pitch_convention': registered['pitch_convention']} if registered else _resource_key(data_dir, role)), 'code': generator.role_cache.code_key()}
+  # Source notation/lyrics also invalidate cached score representation, never the musical seed.
+  key = generator.vocabulary.fingerprint({'inputs': inputs, 'notation': source.document_json})
+  path = pathlib.Path(cache_dir) / role / (key + '.json') if cache_dir else None
+  cached = generator.role_cache.restore(path, key)
+  if cached is not None:
+    return cached
+  started = time.monotonic()
+  document = source.document()
+  part = role.split('_')[0]
+  plan = generator.arrange.form.FormPlan.read(document, part)
+  trace = {'source': source.musical_key, 'role': role, 'production_resources': inputs['catalogs'],
+    'vocabulary': generator.vocabulary.fingerprint(inputs['vocabulary']), 'settings': settings, 'algorithm': algorithm, 'code': inputs['code'], 'cache_key': key}
+  choice_source = source.accompaniment_key() if role.endswith('_accompaniment') else source.musical_key
+  choice_data, choice_settings = inputs['vocabulary'], settings
+  if role.endswith('_accompaniment'):
+    # Voicing weights invalidate the concrete cache, but must not reshuffle
+    # rhythm patterns. Removing this new field preserves the pre-policy seed.
+    choice_data = copy.deepcopy(choice_data)
+    choice_data['roles']['role'].pop('voicing', None)
+    for field in ('provenance', 'license', 'research'):
+      choice_data['accompaniment'].pop(field, None)
+    choice_settings = {k: v for k, v in settings.items() if k != 'voicing'}
+  seed = generator.vocabulary.fingerprint({'source': choice_source, 'role': role, 'settings': choice_settings, 'data': choice_data, 'version': algorithm})
+  details = {}
+  solo_report = ''
+  composition_timings = {}
+  composition = generator.vocabulary.CompositionContext.create(resources, role, settings | {'choice_seed': seed})
+  if role.endswith('_solo'):
+    result = generator.arrange.generate._arrange_document(document, part, plan, owned={'slash'}, composition=composition)
+    si = 3 if part == 'acoustic' else 4
+    first, count, offset, length = generator.solo.arrangement.regions(document)[si]
+    # The template/harmony comes directly from source form, not another generated part.
+    authored = generator.score.source_staff(document)['measures']
+    section = plan.sections[si]
+    effective = generator.arrange.generate.section_source(authored, section, plan.sections[si + 1])
+    template = copy.deepcopy(effective[section.source_measure_index:section.source_measure_index + count])
+    initial = generator.accompaniment.carried_chords(effective)[section.source_measure_index]
+    start, end = next((a - offset, b - offset) for a, b, r in plan.windows if r == role)
+    notation_first = first
+    if start < 0:
+      # The preceding arrangement harmony comes from the source form. Do
+      # not invent harmony from a comparison score's unlabelled lead-in.
+      template.insert(0, copy.deepcopy(result['staves'][0]['measures'][first - 1]))
+      notation_first -= 1
+      initial = generator.accompaniment.carried_chords(result['staves'][0]['measures'])[first - 1]
+    if registered:
+      solo = generator.solo.authored.realize(registered, generator.source.analyze(document), template, part, start, end, initial, composition=composition)
+    else:
+      solo_model = _solo_model(str(data_dir), inputs['catalogs']['model'])
+      solo = generator.solo.composer.compose(generator.source.analyze(document), template, part, end, initial=initial, learned_model=solo_model, expressions_enabled=composition.role().get('expressions', True), start=start, composition=composition)
+    composition_timings = {k: v for k, v in solo.diagnostics.items() if k.endswith('_seconds')}
+    relative = tuple(dataclasses.replace(n, start=n.start - start, end=n.end - start) for n in solo.notes())
+    output = generator.solo.notation.measures(result['staves'][0]['measures'][notation_first:first + count], relative, 'solo_' + part)
+    generator.solo.notation.replace_region(result, notation_first, output)
+    details = generator.solo.report.structure(solo, composition=composition)
+    details['allocation'] = {'start': str(start), 'end': str(end), 'lead_in_measures': first - notation_first}
+    solo_report = generator.solo.report.describe(solo, first, offset, detail=details, composition=composition)
+  elif role.endswith('_accompaniment'):
+    canonical = generator.comping.Canonical(document, part, seed, composition=composition, plan=plan)
+    result = generator.arrange.generate._arrange_document(document, part, plan, owned={'accompaniment'}, accompaniment=canonical, composition=composition)
+    details = {'canonical_comping': canonical.report, 'accompaniment_rhythm': canonical.rhythm_report, 'groove_cycles': canonical.groove_report, 'rhythm_source': choice_source}
+  else:
+    result = generator.arrange.generate._arrange_document(document, part, plan, owned={'vocal' if part == 'vocal' else 'melody'}, composition=composition)
+  allowed = tuple((a, b) for a, b, r in plan.windows if r == role)
+  generator.arrange.assembly.mask(result, allowed)
+  if role == "acoustic_accompaniment":
+    generator.acoustic.validate_comping(result)
+  staff = result['staves'][0]
+  for measure in staff['measures']:
+    measure['id'] = role + '_' + measure['id']
+  staff['tuplets'] = generator.score.reidentify(staff['measures'], staff.get('tuplets', []))
+  if part != 'vocal':
+    result['staves'][0]['tablature'] = True
+  generator.validation.validate_document(result)
+  generator.fretboard.validate_document(result)
+  value = {'role': role, 'document': result, 'trace': trace, 'details': details, 'report': solo_report, 'seconds': time.monotonic() - started, 'composition_timings': composition_timings, 'cache_hit': False}
+  # Sidecar diagnostics use the same rational-safe representation as reports.
+  # Identical insertion order after cold generation and cache loading also
+  # keeps serialized scores and the catalog byte-for-byte reproducible.
+  value = json.loads(json.dumps(value, default=str, sort_keys=True))
+  generator.role_cache.store(path, key, value)
+  return value
diff --git a/generator/composition_types.py b/generator/composition_types.py
new file mode 100644
index 0000000..10fea3c
--- /dev/null
+++ b/generator/composition_types.py
@@ -0,0 +1,28 @@
+"""Worker requests and role results; score serialization stays unchanged."""
+from __future__ import annotations
+import dataclasses
+import pathlib
+import typing
+
+import generator.source
+
+ROLES = ('acoustic_accompaniment', 'electric_accompaniment', 'electric_melody', 'vocal_melody', 'acoustic_solo', 'electric_solo')
+
+@dataclasses.dataclass(frozen=True)
+class RoleRequest:
+  source: generator.source.SourceAnalysis
+  role: str
+  directory: pathlib.Path
+  settings_json: str = '{}'
+  cache: pathlib.Path | None = None
+
+class RoleResult(typing.TypedDict):
+  role: str
+  document: dict
+  trace: dict
+  details: dict
+  report: str
+  seconds: float
+  composition_timings: dict
+  cache_hit: bool
+  observed_reads: typing.NotRequired[list[str]]
diff --git a/generator/engraving/cache.py b/generator/engraving/cache.py
index 8d64dd0..436e291 100644
--- a/generator/engraving/cache.py
+++ b/generator/engraving/cache.py
@@ -9,12 +9,12 @@ import pathlib
 import platform
 import re
 import shutil
-import tempfile
 
 import PIL.Image
 import PIL.ImageChops
 import PIL.features
 
+import generator.cache
 import generator.engraving.validation
 import generator.theme
 
@@ -22,9 +22,10 @@ def renderer_identity(fonts, style) -> dict:
   root = pathlib.Path(__file__).resolve().parents[1]
   versions = {name: importlib.metadata.version(name) for name in ('Pillow', 'fonttools', 'aggdraw')}
   versions.update({name: PIL.features.version(name) for name in PIL.features.get_supported()})
-  sources = [*root.joinpath('engraving').glob('*.py'), root / 'model.py', root / 'performance.py', root / 'harmony.py', root / 'theme.py', root / 'palette.json']
+  sources = generator.cache.source_identity(('generator.engraving.pipeline', 'generator.printing'))
+  sources['palette.json'] = hashlib.sha256((root / 'palette.json').read_bytes()).hexdigest()
   return {'fonts_style': fonts.fingerprint(style), 'python': {'implementation': platform.python_implementation(), 'version': platform.python_version()}, 'dependencies': versions,
-    'sources': {path.relative_to(root).as_posix(): hashlib.sha256(path.read_bytes()).hexdigest() for path in sorted(sources)}}
+    'sources': sources}
 
 def renderer_fingerprint(fonts, style) -> str:
   return hashlib.sha256(json.dumps(renderer_identity(fonts, style), sort_keys=True).encode()).hexdigest()
@@ -46,12 +47,9 @@ def band_fingerprint(notation: str, page, band) -> str:
   context = [notation, page.width, page.height, page.supersampling, dataclasses.asdict(band)]
   return hashlib.sha256(json.dumps(context, sort_keys=True, ensure_ascii=False).encode()).hexdigest()
 
-def has_symlink(path: pathlib.Path) -> bool:
-  return any(parent.is_symlink() for parent in (path, *path.parents))
-
 def restore_pages(entry: pathlib.Path, destination: pathlib.Path, validated_pages: set[str] | None = None) -> list[dict] | None:
   try:
-    if has_symlink(entry) or has_symlink(destination):
+    if generator.cache.has_symlink(entry) or generator.cache.has_symlink(destination):
       return None
     manifest = entry / 'pages.json'
     if manifest.is_symlink():
@@ -76,28 +74,17 @@ def restore_pages(entry: pathlib.Path, destination: pathlib.Path, validated_page
     return None
 
 def store_pages(entry: pathlib.Path, destination: pathlib.Path, pages: list[dict]) -> None:
-  if has_symlink(entry.parent):
-    raise ValueError('engraving cache directories must not be symlinks')
-  entry.parent.mkdir(parents=True, exist_ok=True)
-  if entry.is_symlink() or entry.is_file():
-    entry.unlink(missing_ok=True)
-  entry.mkdir(exist_ok=True)
-  with tempfile.TemporaryDirectory(prefix='.engraving_', dir=entry.parent) as temporary:
-    staged = pathlib.Path(temporary)
+  with generator.cache.stage_entry(entry, '.engraving_') as staged:
     for page in pages:
       shutil.copyfile(destination / page['path'], staged / page['path'])
     (staged / 'pages.json').write_text(json.dumps(pages), encoding='utf-8')
     # Identical keys have identical pages; publish complete files, then the manifest.
-    for name in list(dict.fromkeys(page['path'] for page in pages)) + ['pages.json']:
-      target = entry / name
-      if target.is_dir() and not target.is_symlink():
-        shutil.rmtree(target, ignore_errors=True)
-      (staged / name).replace(target)
+    generator.cache.publish_files(entry, staged, list(dict.fromkeys(page['path'] for page in pages)) + ['pages.json'])
 
 def restore_band(entry: pathlib.Path, key: str, width: int, height: int) -> PIL.Image.Image | None:
   try:
     manifest, asset = entry / 'band.json', entry / 'band.png'
-    if has_symlink(entry) or manifest.is_symlink() or asset.is_symlink():
+    if generator.cache.has_symlink(entry) or manifest.is_symlink() or asset.is_symlink():
       return None
     metadata = json.loads(manifest.read_text(encoding='utf-8'))
     if not isinstance(metadata, dict) or set(metadata) != {'context', 'width', 'height', 'sha256'}:
@@ -122,19 +109,8 @@ def restore_band(entry: pathlib.Path, key: str, width: int, height: int) -> PIL.
     return None
 
 def store_band(entry: pathlib.Path, key: str, image: PIL.Image.Image) -> None:
-  if has_symlink(entry.parent):
-    raise ValueError('engraving cache directories must not be symlinks')
-  entry.parent.mkdir(parents=True, exist_ok=True)
-  if entry.is_symlink() or entry.is_file():
-    entry.unlink()
-  entry.mkdir(exist_ok=True)
-  with tempfile.TemporaryDirectory(prefix='.engraving_', dir=entry.parent) as temporary:
-    staged = pathlib.Path(temporary)
+  with generator.cache.stage_entry(entry, '.engraving_') as staged:
     image.save(staged / 'band.png', format='PNG')
     metadata = {'context': key, 'width': image.width, 'height': image.height, 'sha256': hashlib.sha256((staged / 'band.png').read_bytes()).hexdigest()}
     (staged / 'band.json').write_text(json.dumps(metadata), encoding='utf-8')
-    for name in ('band.png', 'band.json'):
-      target = entry / name
-      if target.is_dir() and not target.is_symlink():
-        shutil.rmtree(target)
-      (staged / name).replace(target)
+    generator.cache.publish_files(entry, staged, ('band.png', 'band.json'))
diff --git a/generator/engraving/layout.py b/generator/engraving/layout.py
index c21271c..0983331 100644
--- a/generator/engraving/layout.py
+++ b/generator/engraving/layout.py
@@ -16,7 +16,7 @@ import generator.engraving.spans
 import generator.engraving.tablature
 import generator.engraving.types
 import generator.harmony
-import generator.model
+import generator.validation
 
 def lyric_text(verse: dict) -> str:
   return ''.join(s['text'] for s in verse['syllables'] if s['kind'] in ('text', 'elision'))
@@ -250,7 +250,7 @@ def paginate(systems, document, fonts, style, *, index=None):
 
 def layout_systems(document: dict, style: generator.engraving.types.Style, fonts: generator.engraving.fonts.Fonts, *, index=None) -> tuple[generator.engraving.types.System, ...]:
   if index is None:
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     index = generator.engraving.notation.ScoreIndex(document)
   if not index.measures:
     raise generator.engraving.types.EngravingError('score has no measures')
@@ -276,7 +276,7 @@ def layout_systems(document: dict, style: generator.engraving.types.Style, fonts
   return tuple(systems)
 
 def layout_score(document: dict, style: generator.engraving.types.Style, fonts: generator.engraving.fonts.Fonts) -> generator.engraving.types.LayoutDocument:
-  generator.model.validate_document(document)
+  generator.validation.validate_document(document)
   style = generator.engraving.types.score_style(document, style)
   index = generator.engraving.notation.ScoreIndex(document)
   systems = layout_systems(document, style, fonts, index=index)
diff --git a/generator/engraving/pipeline.py b/generator/engraving/pipeline.py
index 6b01b00..5c8845c 100644
--- a/generator/engraving/pipeline.py
+++ b/generator/engraving/pipeline.py
@@ -1,195 +1,17 @@
 from __future__ import annotations
 
-import collections
 import concurrent.futures
-import dataclasses
-import hashlib
 import json
 import multiprocessing
 import pathlib
-import shutil
-import tempfile
 import time
 
-import PIL.Image
-
-import generator.engraving.audit
 import generator.engraving.cache
 import generator.engraving.fonts
-import generator.engraving.layout
-import generator.engraving.notation
-import generator.engraving.raster
 import generator.engraving.types
 import generator.engraving.validation
-import generator.model
-import generator.performance
-
-@dataclasses.dataclass
-class GroupResult:
-  scores: list = dataclasses.field(default_factory=list)
-  fullscore: int = 0
-  bodyhits: int = 0
-  bodies: int = 0
-  renderedpages: int = 0
-  rejected: int = 0
-  timings: dict = dataclasses.field(default_factory=lambda: dict.fromkeys(('layout', 'pagination', 'raster', 'cache'), 0.0))
-
-class BodyBands:
-  def __init__(self, root, persistent, result, limit=16 * 1024 * 1024):
-    self.root, self.persistent, self.result, self.limit = root, persistent, result, limit
-    self.images = collections.OrderedDict()
-    self.size = 0
-    self.known = {}
-    self.root.mkdir(parents=True, exist_ok=True)
-  def get(self, notation, page, band, fonts):
-    key = generator.engraving.cache.band_fingerprint(notation, page, band)
-    if key in self.images:
-      self.images.move_to_end(key)
-      self.result.bodyhits += 1
-      return self.images[key]
-    started = time.monotonic()
-    entry = self.root / (key + '.rgb')
-    image = None
-    if key in self.known:
-      if entry.is_symlink() or entry.stat().st_size != page.width * (band.bottom - band.top) * 3:
-        raise generator.engraving.types.EngravingError('temporary notation band was corrupted')
-      data = entry.read_bytes()
-      if hashlib.sha256(data).hexdigest() != self.known[key]:
-        raise generator.engraving.types.EngravingError('temporary notation band was corrupted')
-      image = PIL.Image.frombytes('RGB', (page.width, band.bottom - band.top), data)
-    elif self.persistent:
-      cached = self.persistent / 'notation' / key
-      image = generator.engraving.cache.restore_band(cached, key, page.width, band.bottom - band.top)
-      self.result.rejected += int(image is None and (cached.exists() or cached.is_symlink()))
-    self.result.timings['cache'] += time.monotonic() - started
-    if image is None:
-      started = time.monotonic()
-      image = generator.engraving.raster.rasterize_band(page, band.primitives, band.top, band.bottom, fonts)
-      self.result.timings['raster'] += time.monotonic() - started
-      self.result.bodies += 1
-      if self.persistent:
-        started = time.monotonic()
-        generator.engraving.cache.store_band(self.persistent / 'notation' / key, key, image)
-        self.result.timings['cache'] += time.monotonic() - started
-    else:
-      self.result.bodyhits += 1
-    if key not in self.known:
-      started = time.monotonic()
-      # Spill finalized pixels, so eviction never repeats rasterization or PNG decoding.
-      data = image.tobytes()
-      entry.write_bytes(data)
-      self.result.timings['cache'] += time.monotonic() - started
-      self.known[key] = hashlib.sha256(data).hexdigest()
-    size = image.width * image.height * 3
-    while self.images and self.size + size > self.limit:
-      _, old = self.images.popitem(last=False)
-      self.size -= old.width * old.height * 3
-      old.close()
-    self.images[key] = image
-    self.size += size
-    return image
-  def close(self):
-    for image in self.images.values():
-      image.close()
-    self.images.clear()
-    self.size = 0
-
-def clear_pages(destination):
-  if destination.is_symlink() or destination.is_file():
-    destination.unlink()
-  elif destination.exists():
-    shutil.rmtree(destination)
-
-def write_bundle(path, document, pages, fingerprint):
-  entries = [{k: v for k, v in {**page, 'path': path.with_suffix('.pages').name + '/' + page['path']}.items() if k != 'playback'} for page in pages]
-  normal = [entry for entry, page in zip(entries, pages) if not page['playback']]
-  playback = [entry for entry, page in zip(entries, pages) if page['playback']]
-  music = document
-  bundle = {'music': music, 'presentation': {'engine': generator.engraving.validation.ENGINE_NAME, 'style_sha256': fingerprint,
-    'width': generator.engraving.validation.PAGE_WIDTH, 'height': generator.engraving.validation.PAGE_HEIGHT, 'pages': normal, 'playback_pages': playback}}
-  validate_cached_views(document, pages)
-  bundle['performance'] = generator.performance.timing(document)
-  path.write_text(json.dumps(bundle, indent=2, ensure_ascii=False) + '\n', encoding='utf-8')
-
-def validate_cached_views(document, pages):
-  generator.performance.validate_views(document, [p for p in pages if not p['playback']], [p for p in pages if p['playback']])
-
-def engrave_group(notation, paths, root, font_path, cache_dir, fingerprint, progress=False):
-  family = generator.engraving.fonts.Fonts(font_path)
-  style = generator.engraving.types.Style()
-  systems = None
-  index = None
-  scores = {}
-  audited = set()
-  result = GroupResult()
-  with tempfile.TemporaryDirectory(prefix='vamp_notation_') as temporary:
-    bodies = BodyBands(pathlib.Path(temporary), cache_dir, result)
-    try:
-      for path, score_key in paths:
-        try:
-          document = json.loads(path.read_text(encoding='utf-8'))
-          style = generator.engraving.types.score_style(document, generator.engraving.types.Style())
-          destination = path.with_suffix('.pages')
-          clear_pages(destination)
-          destination.mkdir()
-          if score_key in scores:
-            source, pages = scores[score_key]
-            for page in pages:
-              shutil.copyfile(source / page['path'], destination / page['path'])
-            result.fullscore += 1
-          else:
-            if systems is None:
-              started = time.monotonic()
-              generator.model.validate_document(document)
-              index = generator.engraving.notation.ScoreIndex(document)
-              systems = generator.engraving.layout.layout_systems(document, style, family, index=index)
-              result.timings['layout'] += time.monotonic() - started
-            started = time.monotonic()
-            pages_layout, playback_layout = generator.engraving.layout.page_views(systems, document, family, style, index=index)
-            placement = tuple((page.width, page.height, tuple((system.start, system.end, system.box) for system in page.systems)) for page in pages_layout)
-            if placement not in audited:
-              layout = generator.engraving.types.LayoutDocument(pages_layout, style, fingerprint)
-              generator.engraving.audit.audit_layout(document, layout, family)
-              generator.engraving.audit.audit_playback(pages_layout, playback_layout, style, family)
-              audited.add(placement)
-            else:
-              for page in pages_layout + playback_layout:
-                decoration = tuple(p for p in page.primitives if p.role in ('title', 'subtitle', 'page_number'))
-                generator.engraving.audit.audit_primitives(decoration, page.width, page.height, family)
-            result.timings['pagination'] += time.monotonic() - started
-            pages = []
-            rendered = {}
-            for is_playback, page in [(False, p) for p in pages_layout] + [(True, p) for p in playback_layout]:
-              if page.primitives in rendered:
-                name, digest = rendered[page.primitives]
-                pages.append(dict(path=name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
-                continue
-              bands = generator.engraving.raster.page_bands(page)
-              if bands is None:
-                started = time.monotonic()
-                image = generator.engraving.raster.rasterize_page(page, family)
-              else:
-                body = bodies.get(notation, page, bands[1], family)
-                started = time.monotonic()
-                image = generator.engraving.raster.compose_page(page, family, bands, body)
-              target = destination / (('playback-' if is_playback else '') + f'{page.number:04}.png')
-              with image:
-                image.save(target, format='PNG')
-              result.timings['raster'] += time.monotonic() - started
-              result.renderedpages += 1
-              digest = hashlib.sha256(target.read_bytes()).hexdigest()
-              rendered[page.primitives] = target.name, digest
-              pages.append(dict(path=target.name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
-            scores[score_key] = (destination, pages)
-          write_bundle(path, document, pages, fingerprint)
-          result.scores.append((path, score_key, pages))
-          if progress and len(result.scores) % 50 == 0:
-            print(f'Engraving body {notation[:12]}: {len(result.scores)}/{len(paths)} scores, fullscore {result.fullscore}, bodyhits {result.bodyhits}, bodies {result.bodies}, renderedpages {result.renderedpages}', flush=True)
-        except ValueError as error:
-          raise generator.engraving.types.EngravingError(f'{path.relative_to(root)}: {error}') from error
-    finally:
-      bodies.close()
-  return result
+import generator.engraving.worker
+import generator.validation
 
 def engrave_tree(root: pathlib.Path, fonts: pathlib.Path, *, cache_dir: pathlib.Path | None = None, jobs: int = 1, progress: bool = False) -> set[str]:
   if type(jobs) is not int or not 1 <= jobs <= 16:
@@ -211,22 +33,22 @@ def engrave_tree(root: pathlib.Path, fonts: pathlib.Path, *, cache_dir: pathlib.
       print(f'Engraving cache enabled: {cache_dir} ({state}; renderer {renderer})', flush=True)
   elif progress:
     print('Engraving cache disabled', flush=True)
-  totals = GroupResult()
+  totals = generator.engraving.worker.GroupResult()
   missing, rejected, completed = 0, 0, 0
   groups = {}
   for path in paths:
     try:
       document = json.loads(path.read_text(encoding='utf-8'))
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
       score_key = generator.engraving.cache.score_fingerprint(document, renderer)
       destination = path.with_suffix('.pages')
-      clear_pages(destination)
+      generator.engraving.worker.clear_pages(destination)
       entry = cache_dir / 'fullscore' / score_key if cache_dir else None
       present = entry is not None and (entry.exists() or entry.is_symlink())
       pages = generator.engraving.cache.restore_pages(entry, destination, validated_pages) if entry else None
       if pages is not None:
         try:
-          validate_cached_views(document, pages)
+          generator.engraving.worker.validate_cached_views(document, pages)
         except (ValueError, TypeError, KeyError):
           pages = None
       if pages is None:
@@ -235,7 +57,7 @@ def engrave_tree(root: pathlib.Path, fonts: pathlib.Path, *, cache_dir: pathlib.
         notation = generator.engraving.cache.notation_fingerprint(document, renderer)
         groups.setdefault(notation, []).append((path, score_key))
       else:
-        write_bundle(path, document, pages, fingerprint)
+        generator.engraving.worker.write_bundle(path, document, pages, fingerprint)
         totals.fullscore += 1
         completed += 1
     except ValueError as error:
@@ -272,10 +94,10 @@ def engrave_tree(root: pathlib.Path, fonts: pathlib.Path, *, cache_dir: pathlib.
   jobs = min(jobs, len(groups))
   if jobs <= 1:
     for notation, group in groups.items():
-      finish(engrave_group(notation, group, root, fonts, cache_dir, fingerprint, progress))
+      finish(generator.engraving.worker.engrave_group(notation, group, root, fonts, cache_dir, fingerprint, progress))
   else:
     with concurrent.futures.ProcessPoolExecutor(max_workers=jobs, mp_context=multiprocessing.get_context('spawn')) as pool:
-      futures = [pool.submit(engrave_group, notation, group, root, fonts, cache_dir, fingerprint, progress) for notation, group in groups.items()]
+      futures = [pool.submit(generator.engraving.worker.engrave_group, notation, group, root, fonts, cache_dir, fingerprint, progress) for notation, group in groups.items()]
       for future in concurrent.futures.as_completed(futures):
         finish(future.result())
   if progress:
diff --git a/generator/engraving/worker.py b/generator/engraving/worker.py
new file mode 100644
index 0000000..4128e30
--- /dev/null
+++ b/generator/engraving/worker.py
@@ -0,0 +1,190 @@
+from __future__ import annotations
+
+import collections
+import dataclasses
+import hashlib
+import json
+import pathlib
+import shutil
+import tempfile
+import time
+
+import PIL.Image
+
+import generator.engraving.audit
+import generator.engraving.cache
+import generator.engraving.fonts
+import generator.engraving.layout
+import generator.engraving.notation
+import generator.engraving.raster
+import generator.engraving.types
+import generator.engraving.validation
+import generator.performance
+import generator.validation
+
+@dataclasses.dataclass
+class GroupResult:
+  scores: list = dataclasses.field(default_factory=list)
+  fullscore: int = 0
+  bodyhits: int = 0
+  bodies: int = 0
+  renderedpages: int = 0
+  rejected: int = 0
+  timings: dict = dataclasses.field(default_factory=lambda: dict.fromkeys(('layout', 'pagination', 'raster', 'cache'), 0.0))
+
+class BodyBands:
+  def __init__(self, root, persistent, result, limit=16 * 1024 * 1024):
+    self.root, self.persistent, self.result, self.limit = root, persistent, result, limit
+    self.images = collections.OrderedDict()
+    self.size = 0
+    self.known = {}
+    self.root.mkdir(parents=True, exist_ok=True)
+  def get(self, notation, page, band, fonts):
+    key = generator.engraving.cache.band_fingerprint(notation, page, band)
+    if key in self.images:
+      self.images.move_to_end(key)
+      self.result.bodyhits += 1
+      return self.images[key]
+    started = time.monotonic()
+    entry = self.root / (key + '.rgb')
+    image = None
+    if key in self.known:
+      if entry.is_symlink() or entry.stat().st_size != page.width * (band.bottom - band.top) * 3:
+        raise generator.engraving.types.EngravingError('temporary notation band was corrupted')
+      data = entry.read_bytes()
+      if hashlib.sha256(data).hexdigest() != self.known[key]:
+        raise generator.engraving.types.EngravingError('temporary notation band was corrupted')
+      image = PIL.Image.frombytes('RGB', (page.width, band.bottom - band.top), data)
+    elif self.persistent:
+      cached = self.persistent / 'notation' / key
+      image = generator.engraving.cache.restore_band(cached, key, page.width, band.bottom - band.top)
+      self.result.rejected += int(image is None and (cached.exists() or cached.is_symlink()))
+    self.result.timings['cache'] += time.monotonic() - started
+    if image is None:
+      started = time.monotonic()
+      image = generator.engraving.raster.rasterize_band(page, band.primitives, band.top, band.bottom, fonts)
+      self.result.timings['raster'] += time.monotonic() - started
+      self.result.bodies += 1
+      if self.persistent:
+        started = time.monotonic()
+        generator.engraving.cache.store_band(self.persistent / 'notation' / key, key, image)
+        self.result.timings['cache'] += time.monotonic() - started
+    else:
+      self.result.bodyhits += 1
+    if key not in self.known:
+      started = time.monotonic()
+      # Spill finalized pixels, so eviction never repeats rasterization or PNG decoding.
+      data = image.tobytes()
+      entry.write_bytes(data)
+      self.result.timings['cache'] += time.monotonic() - started
+      self.known[key] = hashlib.sha256(data).hexdigest()
+    size = image.width * image.height * 3
+    while self.images and self.size + size > self.limit:
+      _, old = self.images.popitem(last=False)
+      self.size -= old.width * old.height * 3
+      old.close()
+    self.images[key] = image
+    self.size += size
+    return image
+  def close(self):
+    for image in self.images.values():
+      image.close()
+    self.images.clear()
+    self.size = 0
+
+def clear_pages(destination):
+  if destination.is_symlink() or destination.is_file():
+    destination.unlink()
+  elif destination.exists():
+    shutil.rmtree(destination)
+
+def write_bundle(path, document, pages, fingerprint):
+  entries = [{k: v for k, v in {**page, 'path': path.with_suffix('.pages').name + '/' + page['path']}.items() if k != 'playback'} for page in pages]
+  normal = [entry for entry, page in zip(entries, pages) if not page['playback']]
+  playback = [entry for entry, page in zip(entries, pages) if page['playback']]
+  music = document
+  bundle = {'music': music, 'presentation': {'engine': generator.engraving.validation.ENGINE_NAME, 'style_sha256': fingerprint,
+    'width': generator.engraving.validation.PAGE_WIDTH, 'height': generator.engraving.validation.PAGE_HEIGHT, 'pages': normal, 'playback_pages': playback}}
+  validate_cached_views(document, pages)
+  bundle['performance'] = generator.performance.timing(document)
+  path.write_text(json.dumps(bundle, indent=2, ensure_ascii=False) + '\n', encoding='utf-8')
+
+def validate_cached_views(document, pages):
+  generator.performance.validate_views(document, [p for p in pages if not p['playback']], [p for p in pages if p['playback']])
+
+def engrave_group(notation, paths, root, font_path, cache_dir, fingerprint, progress=False):
+  family = generator.engraving.fonts.Fonts(font_path)
+  style = generator.engraving.types.Style()
+  systems = None
+  index = None
+  scores = {}
+  audited = set()
+  result = GroupResult()
+  with tempfile.TemporaryDirectory(prefix='vamp_notation_') as temporary:
+    bodies = BodyBands(pathlib.Path(temporary), cache_dir, result)
+    try:
+      for path, score_key in paths:
+        try:
+          document = json.loads(path.read_text(encoding='utf-8'))
+          style = generator.engraving.types.score_style(document, generator.engraving.types.Style())
+          destination = path.with_suffix('.pages')
+          clear_pages(destination)
+          destination.mkdir()
+          if score_key in scores:
+            source, pages = scores[score_key]
+            for page in pages:
+              shutil.copyfile(source / page['path'], destination / page['path'])
+            result.fullscore += 1
+          else:
+            if systems is None:
+              started = time.monotonic()
+              generator.validation.validate_document(document)
+              index = generator.engraving.notation.ScoreIndex(document)
+              systems = generator.engraving.layout.layout_systems(document, style, family, index=index)
+              result.timings['layout'] += time.monotonic() - started
+            started = time.monotonic()
+            pages_layout, playback_layout = generator.engraving.layout.page_views(systems, document, family, style, index=index)
+            placement = tuple((page.width, page.height, tuple((system.start, system.end, system.box) for system in page.systems)) for page in pages_layout)
+            if placement not in audited:
+              layout = generator.engraving.types.LayoutDocument(pages_layout, style, fingerprint)
+              generator.engraving.audit.audit_layout(document, layout, family)
+              generator.engraving.audit.audit_playback(pages_layout, playback_layout, style, family)
+              audited.add(placement)
+            else:
+              for page in pages_layout + playback_layout:
+                decoration = tuple(p for p in page.primitives if p.role in ('title', 'subtitle', 'page_number'))
+                generator.engraving.audit.audit_primitives(decoration, page.width, page.height, family)
+            result.timings['pagination'] += time.monotonic() - started
+            pages = []
+            rendered = {}
+            for is_playback, page in [(False, p) for p in pages_layout] + [(True, p) for p in playback_layout]:
+              if page.primitives in rendered:
+                name, digest = rendered[page.primitives]
+                pages.append(dict(path=name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
+                continue
+              bands = generator.engraving.raster.page_bands(page)
+              if bands is None:
+                started = time.monotonic()
+                image = generator.engraving.raster.rasterize_page(page, family)
+              else:
+                body = bodies.get(notation, page, bands[1], family)
+                started = time.monotonic()
+                image = generator.engraving.raster.compose_page(page, family, bands, body)
+              target = destination / (('playback-' if is_playback else '') + f'{page.number:04}.png')
+              with image:
+                image.save(target, format='PNG')
+              result.timings['raster'] += time.monotonic() - started
+              result.renderedpages += 1
+              digest = hashlib.sha256(target.read_bytes()).hexdigest()
+              rendered[page.primitives] = target.name, digest
+              pages.append(dict(path=target.name, sha256=digest, playback=is_playback, **generator.performance.page_timing(document, page)))
+            scores[score_key] = (destination, pages)
+          write_bundle(path, document, pages, fingerprint)
+          result.scores.append((path, score_key, pages))
+          if progress and len(result.scores) % 50 == 0:
+            print(f'Engraving body {notation[:12]}: {len(result.scores)}/{len(paths)} scores, fullscore {result.fullscore}, bodyhits {result.bodyhits}, bodies {result.bodies}, renderedpages {result.renderedpages}', flush=True)
+        except ValueError as error:
+          raise generator.engraving.types.EngravingError(f'{path.relative_to(root)}: {error}') from error
+    finally:
+      bodies.close()
+  return result
diff --git a/generator/guitar.py b/generator/guitar.py
index 727da3f..59d985e 100644
--- a/generator/guitar.py
+++ b/generator/guitar.py
@@ -7,10 +7,10 @@ import itertools
 import logging
 import typing
 
+import generator.chord_families
 import generator.fretboard
 import generator.model
 import generator.pitch
-import generator.chord_families
 import generator.vocabulary
 
 PREFERRED_MAX_FRET = 12
@@ -31,9 +31,10 @@ class VoicingCost(typing.NamedTuple):
   def moved(self, distance: int) -> VoicingCost:
     return self._replace(effort=self.effort + distance)
 
-def voicing_preference(role, center=None):
+def voicing_preference(role, center=None, *, composition=None):
   """Immutable role settings for both selection and scored-retrieval caches."""
-  settings = generator.vocabulary.role(role)
+  composition = composition or generator.vocabulary.current()
+  settings = composition.role(role)
   policy = settings.get('voicing', {})
   center = settings.get('center', 53 if role.startswith('acoustic') else 60) if center is None else center
   result = tuple(fractions.Fraction(str(v)) for v in (center, policy.get('register_weight', 1), policy.get('high_position_weight', 1), policy.get('comfortable_max_fret', 9)))
@@ -50,9 +51,10 @@ def voicing_preferences(positions, preference):
   position = max(fractions.Fraction(), fractions.Fraction(sum(p.fret for p in positions), len(positions)) - threshold)
   return register_weight * register, position_weight * position
 
-def voicing_cost(positions: tuple[generator.fretboard.TabPosition, ...], profile: str = '', allowed: tuple[int, ...] = (), melody: tuple[int, ...] = ()) -> VoicingCost:
-  families = tuple(generator.vocabulary.accompaniment('electric')['voicing_families']['rank'].items()) if profile == 'electric' else ()
-  preference = voicing_preference('electric_melody') if profile == 'electric' and melody else ()
+def voicing_cost(positions: tuple[generator.fretboard.TabPosition, ...], profile: str = '', allowed: tuple[int, ...] = (), melody: tuple[int, ...] = (), *, composition=None) -> VoicingCost:
+  composition = composition or generator.vocabulary.current()
+  families = tuple(composition.accompaniment('electric')['voicing_families']['rank'].items()) if profile == 'electric' else ()
+  preference = voicing_preference('electric_melody', composition=composition) if profile == 'electric' and melody else ()
   return _voicing_cost(positions, profile, allowed, melody, families, preference)
 
 @functools.lru_cache(maxsize=8192)
@@ -69,9 +71,10 @@ def _voicing_cost(positions, profile, allowed, melody, families, preference):
   melody_string = min((p.string_number - 1 for p in positions if melody and p.midi == max(melody)), default=0)
   return VoicingCost(extended_grips=generator.fretboard.span_penalty(positions), melody_string=melody_string, string_shortfall=max(0, 4 - len(positions)) if profile == 'electric' else 0, covered_melody=int(bool(above)), covering_tones=above, family_penalty=family_penalty, effort=effort, missing_tones=len(set(allowed) - classes))
 
-def chord_positions(requirements: generator.fretboard.ChordRequirements, prune: bool = True, profile: str = '', melody: tuple[int, ...] = ()) -> tuple[tuple[generator.fretboard.TabPosition, ...], ...]:
-  families = tuple(generator.vocabulary.accompaniment('electric')['voicing_families']['rank'].items()) if profile == 'electric' else ()
-  preference = voicing_preference('electric_melody') if profile == 'electric' and melody else ()
+def chord_positions(requirements: generator.fretboard.ChordRequirements, prune: bool = True, profile: str = '', melody: tuple[int, ...] = (), *, composition=None) -> tuple[tuple[generator.fretboard.TabPosition, ...], ...]:
+  composition = composition or generator.vocabulary.current()
+  families = tuple(composition.accompaniment('electric')['voicing_families']['rank'].items()) if profile == 'electric' else ()
+  preference = voicing_preference('electric_melody', composition=composition) if profile == 'electric' and melody else ()
   return _chord_positions(requirements, prune, profile, melody, families, preference)
 
 @functools.lru_cache(maxsize=256)
@@ -211,7 +214,8 @@ def continued_sources(notes):
 def has_attack(notes: list[dict]) -> bool:
   return any('_harmony' in n and '_continue_from' not in n or any('tie_from' not in p for p in n['pitches']) for n in notes)
 
-def attack_candidates(notes: list[dict], tones: dict[str, GuitarTone], active: dict, held: dict, preserve_strings: bool, fallback: bool = False):
+def attack_candidates(notes: list[dict], tones: dict[str, GuitarTone], active: dict, held: dict, preserve_strings: bool, fallback: bool = False, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   pending = []
   chords = [n for n in notes if '_harmony' in n]
   chord = chords[0] if chords else None
@@ -229,7 +233,7 @@ def attack_candidates(notes: list[dict], tones: dict[str, GuitarTone], active: d
   requirements = generator.fretboard.chord_requirements(chord['_harmony'], respect_bass=profile != 'electric') if chord else generator.fretboard.ChordRequirements()
   melody = tuple(sorted({p.midi for _, options in pending for p in options})) if profile == 'electric' else ()
   fresh = has_attack(notes)
-  candidates = chord_positions(requirements, prune=not (preserve_strings or held or pending or profile), profile=profile, melody=melody) if chord else [()]
+  candidates = chord_positions(requirements, prune=not (preserve_strings or held or pending or profile), profile=profile, melody=melody, composition=composition) if chord else [()]
   for exact in extend_positions(held, sorted(pending, key=lambda p: len(p[1]))):
     exact_positions = dict(exact)
     for positions in candidates:
@@ -253,7 +257,7 @@ def attack_candidates(notes: list[dict], tones: dict[str, GuitarTone], active: d
           choices.append(EventPlacement(note, tuple((p, exact_positions[p['id']]) for p in note['pitches']), added))
         if not compatible or not playable_choices(choices):
           continue
-        cost = voicing_cost(positions, profile, requirements.allowed, melody) if fresh else VoicingCost()
+        cost = voicing_cost(positions, profile, requirements.allowed, melody, composition=composition) if fresh else VoicingCost()
         yield AttackCandidate(tuple(sorted(assignment.items())), tuple(choices), positions, cost)
       else:
         shape = tuple(p for _, p in exact) + positions
@@ -263,7 +267,7 @@ def attack_candidates(notes: list[dict], tones: dict[str, GuitarTone], active: d
         choices = tuple(EventPlacement(n, tuple((p, exact_positions[p['id']]) for p in n['pitches']), positions if n is chord else ()) for n in notes)
         if not playable_choices(choices):
           continue
-        cost = voicing_cost(shape, profile, requirements.allowed, melody) if fresh else VoicingCost()
+        cost = voicing_cost(shape, profile, requirements.allowed, melody, composition=composition) if fresh else VoicingCost()
         yield AttackCandidate(assignment, choices, shape, cost)
 
 def guitar_events(document: dict) -> tuple[list, dict[str, GuitarTone]]:
@@ -325,7 +329,8 @@ def advance_attacks(candidates, states: dict) -> dict:
       result[candidate.active] = Placement(cost, candidate.active, previous, candidate.choices)
   return result
 
-def advance_positions(notes: list[dict], onset: fractions.Fraction, tones: dict[str, GuitarTone], states: dict, preserve_strings: bool, fallback: bool = False) -> dict:
+def advance_positions(notes: list[dict], onset: fractions.Fraction, tones: dict[str, GuitarTone], states: dict, preserve_strings: bool, fallback: bool = False, *, composition=None) -> dict:
+  composition = composition or generator.vocabulary.current()
   continued = continued_sources(notes)
   fresh = has_attack(notes)
   held_ids = {i for previous in states.values() for i, _ in previous.active if retain_tone(tones[i], onset)}
@@ -337,29 +342,30 @@ def advance_positions(notes: list[dict], onset: fractions.Fraction, tones: dict[
       result[candidate.active] = Placement(cost, candidate.active, previous, candidate.choices)
 
   if not held_ids and not continued:
-    result = advance_attacks(attack_candidates(notes, tones, {}, {}, preserve_strings, fallback), states)
+    result = advance_attacks(attack_candidates(notes, tones, {}, {}, preserve_strings, fallback, composition=composition), states)
   else:
     for previous in states.values():
       active = dict(previous.active)
       held = {i: p for i, p in previous.active if i not in continued and i in held_ids}
-      for candidate in attack_candidates(notes, tones, active, held, preserve_strings, fallback):
+      for candidate in attack_candidates(notes, tones, active, held, preserve_strings, fallback, composition=composition):
         distance = movement(tuple(p for _, p in previous.active), candidate.shape) if fresh else 0
         keep(candidate, previous, previous.cost.moved(distance))
   if not result:
     if not fallback and any(n.get('_harmonize') for n in notes):
-      return advance_positions(notes, onset, tones, states, preserve_strings, True)
+      return advance_positions(notes, onset, tones, states, preserve_strings, True, composition=composition)
     raise ValueError(f'event {notes[0]["id"]}, onset {onset}: no guitar placement; single notes need frets {generator.fretboard.MIN_FRET}-{generator.fretboard.MAX_SINGLE_FRET}; chords need frets {generator.fretboard.MIN_FRET}-{generator.fretboard.MAX_FRET}, an anchor <= {generator.fretboard.MAX_ANCHOR_FRET}, and at most {generator.fretboard.MAX_FRET_SPAN} consecutive fret positions; held/tied strings must remain fixed')
   return result
 
-def place_guitar(document: dict) -> None:
+def place_guitar(document: dict, *, composition=None) -> None:
   """Choose electric voicings or exact/held melody placements."""
+  composition = composition or generator.vocabulary.current()
   events, tones = guitar_events(document)
   states = {(): Placement(VoicingCost(), (), None, ())}
   groups = [(key[0], [item[3] for item in values]) for key, values in itertools.groupby(events, key=lambda e: e[:3])]
   for index, (onset, notes) in enumerate(groups):
     next_onset = groups[index + 1][0] if index + 1 < len(groups) else None
     preserve_strings = next_onset is not None and any('_harmony' in n and onset + generator.model.fraction(n['duration']) > next_onset for n in notes)
-    states = advance_positions(notes, onset, tones, states, preserve_strings)
+    states = advance_positions(notes, onset, tones, states, preserve_strings, composition=composition)
   selected = min(states.values(), key=lambda s: (s.cost, s.active))
   skipped = []
   while selected.previous is not None:
diff --git a/generator/model.py b/generator/model.py
index 76e403f..b701979 100644
--- a/generator/model.py
+++ b/generator/model.py
@@ -3,8 +3,6 @@ from __future__ import annotations
 import copy
 import fractions
 import typing
-import generator.fretboard
-import generator.pitch
 
 MAX_INTEGER = (1 << 63) - 1
 NOTE_TYPES = ('maxima', 'long', 'breve', 'whole', 'half', 'quarter', 'eighth', '16th', '32nd', '64th', '128th', '256th', '512th', '1024th')
@@ -140,157 +138,3 @@ def make_event(identifier: str, onset: fractions.Fraction, duration: fractions.F
     if 'alter' in event['pitches'][-1]:
       event['pitches'][-1]['alter'] = rational(alteration(p['alter']))
   return event
-
-def validate_document(document: dict) -> None:
-  if not isinstance(document, dict) or not isinstance(document.get('metadata'), dict):
-    raise ValueError('score requires a metadata object')
-  if any(not isinstance(document['metadata'].get(name), str) for name in ('title', 'composer', 'key_signature', 'time_signature')):
-    raise ValueError('score metadata requires title, composer, key_signature and time_signature strings')
-  staves = document.get('staves', [])
-  if not isinstance(staves, list) or len(staves) != 1 or not isinstance(staves[0], dict):
-    raise ValueError('exactly one staff is currently supported')
-  if not isinstance(staves[0].get('measures'), list) or not staves[0]['measures']:
-    raise ValueError('score requires measures')
-  instruments = staves[0].get('instruments', [])
-  instrument_ids = {i['id'] for i in instruments}
-  if len(instruments) != len(instrument_ids) or any(not isinstance(i, str) or not i for i in instrument_ids):
-    raise ValueError('score instruments require unique nonempty IDs')
-  ids: set[str] = set()
-  events: dict[str, dict] = {}
-  tones: dict[str, tuple[dict, fractions.Fraction, fractions.Fraction, str]] = {}
-  ownership: dict[str, str] = {}
-  absolute = fractions.Fraction()
-  for measure in staves[0]['measures']:
-    if {'repeats', 'endings', 'initial_attributes'} & measure.keys():
-      raise ValueError('repeat notation is unsupported; regenerate scores from music written out in reading order')
-    length = fraction(measure['duration'])
-    if length <= 0:
-      raise ValueError('measure duration must be positive')
-    voices = measure.get('voices', [])
-    if not voices or len({v['id'] for v in voices}) != len(voices) or any(not v['id'] for v in voices):
-      raise ValueError('measure requires uniquely identified voice lanes')
-    previous_ends = {v['id']: fractions.Fraction() for v in voices}
-    for voice, note in ((v, n) for v in voices for n in v['notes']):
-      if any({'sound_ties', 'printed_ties'} & pitch.keys() for pitch in note['pitches']):
-        raise ValueError('pass-specific tie metadata is unsupported; regenerate scores')
-      if not note['id'] or note['id'] in ids:
-        raise ValueError(f'duplicate event ID: {note["id"]}')
-      ids.add(note['id'])
-      events[note['id']] = note
-      ownership[note['id']] = voice['id']
-      if note.get('voice', voice['id']) != voice['id']:
-        raise ValueError('event voice ownership disagrees with its lane')
-      onset, duration = fraction(note['onset']), fraction(note['duration'])
-      if onset < 0 or duration < 0 or onset + duration > length:
-        raise ValueError(f'event outside measure: {note["id"]}')
-      if note['kind'] not in ('note', 'rest', 'spacer'):
-        raise ValueError('invalid event kind')
-      if not note.get('grace'):
-        if duration == 0 or onset < previous_ends[voice['id']]:
-          raise ValueError('overlapping events in one rhythmic voice')
-        previous_ends[voice['id']] = onset + duration
-      elif duration != 0:
-        raise ValueError('grace notes must not advance metric time')
-      expected = metric_length(note['written'])
-      if not note.get('grace') and not note.get('measure_rest') and duration != expected:
-        raise ValueError('metric and written event durations disagree')
-      if note['kind'] != 'note' and note.get('pitches'):
-        raise ValueError('rests and spacers cannot contain pitches')
-      if note['kind'] == 'note' and not note.get('pitches') and note.get('notehead') != 'slash':
-        raise ValueError('pitched event requires at least one pitch')
-      for p in note.get('pitches', []):
-        if p.get('instrument') and p['instrument'] not in instrument_ids:
-          raise ValueError('note refers to an unknown score instrument')
-        if 'unpitched' in p:
-          position = p['unpitched']
-          if position['letter'] not in LETTERS or type(position['octave']) is not int:
-            raise ValueError('invalid unpitched display position')
-        else:
-          pitch_number(p)
-        if staves[0].get('tablature'):
-          tab = p.get('tablature', {})
-          string, fret = tab.get('string'), tab.get('fret')
-          if type(string) is not int or type(fret) is not int or string not in dict(generator.fretboard.STANDARD_TUNING) or not generator.fretboard.MIN_FRET <= fret <= generator.fretboard.MAX_FRET:
-            raise ValueError(f'{p["id"]}: invalid generated tablature position')
-          state = dict(measure)
-          for change in measure.get('attributes', []):
-            if fraction(change['onset']) <= onset:
-              state.update(change)
-          if dict(generator.fretboard.STANDARD_TUNING)[string] + fret != generator.pitch.sounding_pitch(p, state):
-            raise ValueError(f'{p["id"]}: tablature disagrees with sounding pitch')
-        pd = fraction(p['duration'])
-        if pd < 0 or (pd == 0 and not note.get('grace')) or pd > duration or not p['id'] or p['id'] in tones:
-          raise ValueError('invalid chord-tone duration or duplicate ID')
-        if not note.get('grace') and pd != metric_length(p['written']):
-          raise ValueError('metric and written chord-tone durations disagree')
-        tones[p['id']] = (p, absolute + onset, pd, voice['id'])
-    for harmony in measure.get('harmonies', []):
-      if not 0 <= fraction(harmony['onset']) < length:
-        raise ValueError('harmony outside measure')
-    for change in measure.get('attributes', []):
-      if not 0 <= fraction(change['onset']) < length:
-        raise ValueError('attribute change outside measure')
-    for state in [measure, *measure.get('attributes', [])]:
-      if 'meter' in state:
-        validate_meter(state['meter'])
-      if 'key' in state:
-        if len(state['key']['alterations']) != 7:
-          raise ValueError('key alterations must contain seven exact alterations')
-        for value in state['key']['alterations']:
-          alteration(value)
-      if 'clef' in state and (state['clef']['sign'] not in ('G', 'F', 'C', 'percussion', 'none') or not 1 <= state['clef']['line'] <= 6 or not -3 <= state['clef']['octave_change'] <= 3):
-        raise ValueError('invalid clef')
-    absolute += length
-  for identifier, (p, start, duration, voice) in tones.items():
-    if target := p.get('tie_to'):
-      if target not in tones:
-        raise ValueError(f'dangling tie: {identifier} -> {target}')
-      other, next_start, _, next_voice = tones[target]
-      same_pitch = all(p.get(k) == other.get(k) for k in ('unpitched', 'instrument')) if 'unpitched' in p else all(p.get(k) == other.get(k) for k in ('letter', 'alter', 'octave'))
-      if other.get('tie_from') != identifier or not same_pitch or next_voice != voice or next_start != start + duration:
-        raise ValueError(f'invalid tie: {identifier} -> {target}')
-      if staves[0].get('tablature') and p['tablature'] != other['tablature']:
-        raise ValueError(f'{identifier}: tied guitar tones must retain their string and fret')
-    if source := p.get('tie_from'):
-      if source not in tones or tones[source][0].get('tie_to') != identifier:
-        raise ValueError(f'dangling incoming tie: {identifier}')
-  span_ids = set()
-  event_order = {identifier: index for index, identifier in enumerate(events)}
-  for span in staves[0].get('tuplets', []):
-    if not span['id'] or span['id'] in span_ids or span['start'] not in ids or span['end'] not in ids or not 0 < span['note_count'] <= 1000000 or not 0 < span['space_count'] <= 1000000 or not 0 <= span['depth'] <= 16:
-      raise ValueError('invalid tuplet span')
-    members = [n['id'] for n in events.values() if span['id'] in n.get('tuplet_ids', [])]
-    if not members or members[0] != span['start'] or members[-1] != span['end'] or event_order[span['start']] > event_order[span['end']]:
-      raise ValueError('tuplet endpoints disagree with member events')
-    if len({ownership[n] for n in members}) != 1 or span.get('voice', ownership[members[0]]) != ownership[members[0]]:
-      raise ValueError('tuplet crosses independent voice lanes')
-    if span.get('bracket', 'auto') not in ('yes', 'no', 'auto') or span.get('show_number', 'actual') not in ('none', 'actual', 'both'):
-      raise ValueError('invalid tuplet appearance')
-    span_ids.add(span['id'])
-  for note in events.values():
-    for verse in note.get('lyrics', []):
-      start = tones[note['pitches'][0]['id']][1] if note['pitches'] else fractions.Fraction()
-      if 'extend_to' in verse and not start < fraction(verse['extend_to']) <= absolute:
-        raise ValueError('lyric extension endpoint is outside the score')
-    if any(t not in span_ids for t in note.get('tuplet_ids', [])):
-      raise ValueError('event refers to an unknown tuplet')
-    if tremolo := note.get('tremolo'):
-      if tremolo['type'] not in ('single', 'start', 'stop') or type(tremolo['marks']) is not int or not 0 <= tremolo['marks'] <= 8:
-        raise ValueError('invalid measured tremolo')
-      if tremolo['type'] in ('start', 'stop'):
-        other = events.get(tremolo.get('partner'))
-        expected_type = 'stop' if tremolo['type'] == 'start' else 'start'
-        if not other or other.get('tremolo', {}).get('partner') != note['id'] or other['tremolo']['type'] != expected_type or other['tremolo']['marks'] != tremolo['marks']:
-          raise ValueError('invalid paired tremolo')
-  for span in staves[0].get('octave_shifts', []):
-    if not 0 <= fraction(span['start']) < fraction(span['end']) <= absolute or not -3 <= span['octaves'] <= 3:
-      raise ValueError('invalid octave-shift span')
-  previous_end = fractions.Fraction()
-  for span in staves[0].get('scale_spans', []):
-    start, end = fraction(span['start']), fraction(span['end'])
-    if not previous_end <= start < end <= absolute or not isinstance(span.get('label'), str) or not span['label'].strip() or type(span.get('matched')) is not bool:
-      raise ValueError('invalid solo scale span')
-    if not isinstance(span.get('id'), str) or not span['id'] or span['id'] in ids:
-      raise ValueError('solo scale spans require unique IDs')
-    ids.add(span['id'])
-    previous_end = end
diff --git a/generator/musicxml.py b/generator/musicxml.py
index e5aaca4..6878fa0 100644
--- a/generator/musicxml.py
+++ b/generator/musicxml.py
@@ -8,6 +8,7 @@ import defusedxml.ElementTree
 
 import generator.harmony
 import generator.model
+import generator.validation
 
 class MusicXMLError(ValueError):
   pass
@@ -621,7 +622,7 @@ class Importer:
     metadata.update({'key_signature': measures[0]['key_signature'], 'time_signature': measures[0]['time_signature'], 'key': copy.deepcopy(measures[0]['key'])})
     result = {'metadata': metadata, 'staves': [{'id': 'staff_source', 'name': definitions[0].findtext('part-name', 'Source'), 'role': 'vocal', 'clef': copy.deepcopy(measures[0]['clef']), 'tuplets': self.tuplets, 'octave_shifts': self.octaves, 'measures': measures}]}
     result['staves'][0]['instruments'] = instruments
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     return result
 
 def load_musicxml(path: pathlib.Path) -> dict:
diff --git a/generator/musicxml_writer.py b/generator/musicxml_writer.py
index 5c48ff7..1730f52 100644
--- a/generator/musicxml_writer.py
+++ b/generator/musicxml_writer.py
@@ -7,6 +7,7 @@ import xml.etree.ElementTree
 
 import generator.harmony
 import generator.model
+import generator.validation
 
 def element(parent, tag, content=None, **attributes):
   node = xml.etree.ElementTree.SubElement(parent, tag, {k.replace('_', '-'): str(v) for k, v in attributes.items() if v is not None})
@@ -209,7 +210,7 @@ def write_barline(bar, measure, location):
   element(node, 'bar-style', measure.get('barlines', {}).get(location, 'regular'))
 
 def musicxml_tree(document: dict, *, tablature=False) -> xml.etree.ElementTree.ElementTree:
-  generator.model.validate_document(document)
+  generator.validation.validate_document(document)
   root = xml.etree.ElementTree.Element('score-partwise', {'version': '4.0'})
   metadata, staff = document['metadata'], document['staves'][0]
   element(element(root, 'work'), 'work-title', metadata['title'])
diff --git a/generator/parts.py b/generator/parts.py
index 518afa3..3a2da69 100644
--- a/generator/parts.py
+++ b/generator/parts.py
@@ -3,7 +3,6 @@ from __future__ import annotations
 import fractions
 import pathlib
 
-import generator.accompaniment
 import generator.fretboard
 import generator.model
 import generator.pitch
diff --git a/generator/performance.py b/generator/performance.py
index 1d668ad..836f071 100644
--- a/generator/performance.py
+++ b/generator/performance.py
@@ -1,14 +1,8 @@
-"""Page timing and supplied recordings. No note synthesis or audio transformation."""
+"""Pure page coverage and performance timing."""
 from __future__ import annotations
 
 import fractions
-import hashlib
-import json
 import math
-import pathlib
-import re
-import shutil
-import wave
 
 import generator.model
 
@@ -117,57 +111,3 @@ def timing(document):
   return dict(song_id=document['metadata'].get('song_id', ''),
     duration=generator.model.rational(times[-1]),
     sustain_start=generator.model.rational(sustain_start), count_in_beats=4, clicks=clicks)
-
-def describe_wav(path, root, *, song_id='', bpm=0):
-  if path.is_symlink() or not path.is_file() or not path.resolve().is_relative_to(root.resolve()):
-    raise ValueError(f'{path}: expected a contained regular WAV')
-  try:
-    with wave.open(str(path), 'rb') as audio:
-      channels, rate, frames = audio.getnchannels(), audio.getframerate(), audio.getnframes()
-      if audio.getcomptype() != 'NONE' or audio.getsampwidth() != 2 or channels not in (1, 2) or not 8000 <= rate <= 192000 or frames <= 0:
-        raise ValueError('expected nonempty mono/stereo PCM16 WAV')
-      remaining = frames
-      while remaining:
-        count = min(remaining, 65536)
-        if len(audio.readframes(count)) != count * channels * 2:
-          raise ValueError('truncated WAV data')
-        remaining -= count
-  except (wave.Error, EOFError) as error:
-    raise ValueError(f'{path}: invalid WAV: {error}') from error
-  with path.open('rb') as source:
-    digest = hashlib.file_digest(source, 'sha256').hexdigest()
-  return dict(path=path.relative_to(root).as_posix(), sha256=digest, channels=channels, sample_rate=rate, frames=frames, song_id=song_id, bpm=bpm)
-
-def copy_audio(static, destination, song_ids):
-  entries = []
-  inputs = [(static / 'sounds' / name, '', 0) for name in ('beat1.wav', 'beat2.wav')]
-  for path in sorted((static / 'backing').glob('*.wav')):
-    match = re.fullmatch(r'([a-z0-9]+(?:_[a-z0-9]+)*)_(60|70|80|90|100|110|120)\.wav', path.name)
-    if not match:
-      raise ValueError(f'{path}: unsupported backing filename or tempo')
-    if match[1] not in song_ids:
-      continue
-    inputs.append((path, match[1], int(match[2])))
-  for source, song_id, bpm in inputs:
-    description = describe_wav(source, static, song_id=song_id, bpm=bpm)
-    target = destination / description['path']
-    target.parent.mkdir(parents=True, exist_ok=True)
-    shutil.copyfile(source, target)
-    entries.append(description)
-  return entries
-
-def validate_recording_lengths(root, entries):
-  durations = {}
-  for path in sorted((root / 'songs').glob('*.json')):
-    document = json.loads(path.read_text())
-    performance = timing(document)
-    song_id = performance['song_id']
-    duration = generator.model.fraction(performance['duration']) + performance['count_in_beats']
-    if song_id in durations and durations[song_id] != duration:
-      raise ValueError(f'{song_id}: parts disagree about performance duration')
-    durations[song_id] = duration
-  for entry in entries:
-    if entry['song_id']:
-      seconds = fractions.Fraction(entry['frames'], entry['sample_rate'])
-      if seconds < durations[entry['song_id']] * 60 / entry['bpm']:
-        raise ValueError(f"{entry['path']}: backing recording is shorter than count-in and score")
diff --git a/generator/printing.py b/generator/printing.py
index 96cad0f..11bfc26 100644
--- a/generator/printing.py
+++ b/generator/printing.py
@@ -7,7 +7,6 @@ import json
 import math
 import pathlib
 import shutil
-import tempfile
 import time
 
 import PIL.PdfParser
@@ -19,7 +18,7 @@ import generator.engraving.layout
 import generator.engraving.notation
 import generator.engraving.raster
 import generator.engraving.types
-import generator.model
+import generator.validation
 
 # Two layout units per PDF point: guitar staff spacing is five points.
 # Raster resolution is independent of layout and the device's display theme.
@@ -30,7 +29,7 @@ MEDIA_BOX = [0, 0, 612, 792]
 VERSION = 'letter-parts-v1'
 
 def layout_part(document, fonts):
-  generator.model.validate_document(document)
+  generator.validation.validate_document(document)
   style = dataclasses.replace(generator.engraving.types.score_style(document, STYLE), system_gap=STYLE.system_gap)
   # Measure numbers are centered over barlines and can extend left of the
   # staff. Reserve their actual overhang inside the half-inch paper margin.
@@ -123,7 +122,7 @@ def renderer_key(fonts):
 
 def restore(entry, key, target):
   try:
-    if generator.engraving.cache.has_symlink(entry):
+    if generator.cache.has_symlink(entry):
       return None
     pdf, manifest = entry / 'part.pdf', entry / 'print.json'
     if pdf.is_symlink() or manifest.is_symlink():
@@ -138,21 +137,10 @@ def restore(entry, key, target):
     return None
 
 def store(entry, key, target, pages):
-  if generator.engraving.cache.has_symlink(entry.parent):
-    raise ValueError('print cache must not contain symlinks')
-  entry.parent.mkdir(parents=True, exist_ok=True)
-  if entry.is_symlink() or entry.is_file():
-    entry.unlink()
-  entry.mkdir(exist_ok=True)
-  with tempfile.TemporaryDirectory(prefix='.print_', dir=entry.parent) as temporary:
-    staged = pathlib.Path(temporary)
+  with generator.cache.stage_entry(entry, '.print_') as staged:
     shutil.copyfile(target, staged / 'part.pdf')
     (staged / 'print.json').write_text(json.dumps({'key': key, 'sha256': hashlib.sha256(target.read_bytes()).hexdigest(), 'pages': pages}))
-    for name in ('part.pdf', 'print.json'):
-      destination = entry / name
-      if destination.is_dir() and not destination.is_symlink():
-        shutil.rmtree(destination)
-      (staged / name).replace(destination)
+    generator.cache.publish_files(entry, staged, ('part.pdf', 'print.json'))
 
 def generate_tree(root, font_path, *, cache_dir=None, progress=False):
   """Called inside the normal build's atomic staging directory."""
diff --git a/generator/production.py b/generator/production.py
index e653452..acd92a2 100644
--- a/generator/production.py
+++ b/generator/production.py
@@ -1,342 +1,23 @@
-"""Independent, reproducible role generation and non-composing assembly.
-
-Only source documents and production resources enter generate_role. Completed
-roles and published assets are downstream values, never composition inputs.
-"""
+"""File discovery, process scheduling and publication of independent roles."""
 from __future__ import annotations
 import concurrent.futures
 import copy
-import dataclasses
-import hashlib
-import functools
 import json
 import multiprocessing
-import os
 import pathlib
-import tempfile
-import time
-import fractions
 
-import generator.accompaniment
-import generator.comping
-import generator.fretboard
-import generator.model
+import generator.arrange.accompaniment
+import generator.arrange.assembly
+import generator.composition
+import generator.composition_types
 import generator.musicxml
 import generator.parts
 import generator.score
-import generator.vocabulary
-import generator.arrange.accompaniment
-import generator.arrange.ending
-import generator.arrange.form
-import generator.arrange.generate
-import generator.arrange.pickup
-import generator.solo.analysis
-import generator.solo.composer
-import generator.solo.notation
-import generator.solo.report
-import generator.solo.learned
-import generator.solo.authored
-import generator.input_audit
-import generator.solo.arrangement
-
-VERSION = 'independent-roles-1'
-ROLES = ('acoustic_accompaniment', 'electric_accompaniment', 'electric_melody', 'vocal_melody', 'acoustic_solo', 'electric_solo')
-
-@dataclasses.dataclass(frozen=True)
-class SourceAnalysis:
-  document_json: str
-  musical_key: str
-  @classmethod
-  def read(cls, document):
-    prepared = copy.deepcopy(document)
-    staff = generator.score.source_staff(prepared)
-    for i, m in enumerate(staff['measures']):
-      m['id'], m['number'] = f'source_{i}', str(i + 1)
-    staff['tuplets'] = generator.score.reidentify(staff['measures'], staff.get('tuplets', []))
-    prepared['metadata'] = {k: v for k, v in prepared['metadata'].items() if k not in ('title', 'composer', 'copyright', 'software')}
-    prepared['metadata'].update(title='Source', composer='')
-    staff.update(id='source', name='Source')
-    melodic = generator.solo.analysis.analyze(prepared)
-    content = {'melody': [(str(n.start), str(n.end), dataclasses.asdict(n.pitch)) for n in melodic.melody],
-      'measures': [{k: m.get(k) for k in ('duration', 'time_signature', 'key', 'harmonies', 'tempos', 'section_label', 'implicit')} for m in staff['measures']]}
-    # Fraction/string spelling is canonical and never includes filesystem IDs.
-    key = hashlib.sha256(json.dumps(content, sort_keys=True, default=str).encode()).hexdigest()
-    return cls(json.dumps(prepared, sort_keys=True), key)
-  def document(self):
-    return json.loads(self.document_json)
-  def accompaniment_key(self):
-    document = self.document()
-    document['metadata'].pop('tempo', None)
-    for measure in generator.score.source_staff(document)['measures']:
-      measure['tempos'] = []
-    return SourceAnalysis.read(document).musical_key
-
-def windows(document, part):
-  source = generator.score.source_staff(document)['measures']
-  sections = generator.arrange.form.full_arrangement_sections(source, part)
-  result, cursor = [], fractions.Fraction()
-  for section in sections:
-    duration = sum((generator.model.fraction(m['duration']) for m in source[section.source_measure_index:section.source_measure_index + section.measure_count]), fractions.Fraction())
-    role = {'slash': 'solo', 'vocal': 'melody'}.get(section.role, section.role)
-    if section.role in ('vocal', 'melody') and generator.arrange.pickup.enters(section, source) and result:
-      attacks = [generator.model.fraction(n['onset']) for n in generator.score.measure_notes(source[0]) if n['pitches']]
-      if attacks:
-        start = cursor - generator.model.fraction(source[0]['duration']) + min(attacks)
-        a, _, old = result[-1]
-        result[-1] = (a, start, old)
-        result.append((start, cursor, part + '_' + role))
-    end = cursor + duration
-    start = cursor
-    if section.role == 'slash' and generator.score.body_start_measure_index(source) and result:
-      # Allocate the source's complete pickup bar before composition. This
-      # does not inspect either generated solo; a role may leave it silent.
-      start = cursor - generator.model.fraction(source[0]['duration'])
-      a, _, old = result[-1]
-      result[-1] = (a, start, old)
-    result.append((start, end, part + '_' + role))
-    cursor = end
-  result.append((cursor, cursor + generator.arrange.ending.duration(source), part + ('_accompaniment' if part != 'vocal' else '_rest')))
-  return tuple(result)
-
-def dependencies(role, resources, measures=None):
-  names = ['harmony', 'lead_ins'] if role.endswith('_solo') else []
-  accompaniment = {}
-  if role.endswith('_accompaniment'):
-    policy = generator.vocabulary.accompaniment(role.split('_')[0], resources)
-    accompaniment = {'accompaniment': generator.comping_rhythm.relevant_policy(policy, measures) if measures is not None else policy}
-  return {'roles': {'role': resources['roles']['roles'][role], 'difficulty': resources['roles']['difficulty']},
-    **({'voicing_families': generator.vocabulary.accompaniment('electric', resources)['voicing_families']} if role == 'electric_melody' else {}),
-    **accompaniment,
-    **{name: resources[name] for name in names}}
-
-def _code_key(role):
-  root = pathlib.Path(__file__).parent
-  paths = [root / n for n in ('production.py', 'model.py', 'harmony.py', 'pitch.py', 'fretboard.py', 'parts.py', 'score.py', 'vocabulary.py')]
-  paths += list((root / 'arrange').glob('*.py'))
-  if role.endswith('_solo'):
-    paths += list((root / 'solo').glob('*.py'))
-    paths += [root / 'harmonic_time.py', root / 'musicxml.py', root / 'training_io.py']
-  elif role.endswith('_accompaniment'):
-    paths += [root / n for n in ('comping.py', 'comping_rhythm.py', 'chord_families.py', 'accompaniment.py', 'guitar.py')]
-    if role == 'acoustic_accompaniment':
-      paths += [root / 'acoustic_voicing.py', root / 'acoustic.py']
-  elif role == 'electric_melody':
-    paths += [root / 'guitar.py', root / 'melody.py', root / 'chord_families.py']
-  return generator.vocabulary.fingerprint([(p.relative_to(root).as_posix(), hashlib.sha256(p.read_bytes()).hexdigest()) for p in sorted(set(paths))])
-
-def _resource_key(directory, role):
-  return {'model': hashlib.sha256((directory / 'models' / 'solo.json').read_bytes()).hexdigest()} if role.endswith('_solo') else {}
-
-@functools.lru_cache(maxsize=4)
-def _solo_model(directory, fingerprint):
-  return generator.solo.learned.Model.load(pathlib.Path(directory) / 'models' / 'solo.json')
-
-def _mask(document, allowed):
-  """Apply source-defined role exclusions, without observing another part."""
-  absolute = fractions.Fraction()
-  for measure in document['staves'][0]['measures']:
-    length = generator.model.fraction(measure['duration'])
-    for voice in measure['voices']:
-      selected = []
-      for n in voice['notes']:
-        start = absolute + generator.model.fraction(n['onset'])
-        end = start + generator.model.fraction(n['duration'])
-        intervals = [(max(start, a), min(end, b)) for a, b in allowed if a < end and b > start]
-        for a, b in intervals:
-          note = copy.deepcopy(n)
-          if a != start:
-            note['onset'] = generator.model.rational(a - absolute)
-            for pitch in note['pitches']:
-              pitch.pop('tie_from', None)
-          generator.arrange.pickup.truncate(note, b - absolute)
-          if a < b:
-            selected.append(note)
-      voice['notes'] = _fill(selected, length, measure['id'] + '_' + voice['id'], voice['id'])
-    absolute += length
-  staff = document['staves'][0]
-  staff['tuplets'] = generator.arrange.pickup.retain_links(staff['measures'], staff.get('tuplets', []))
-
-def _fill(notes, length, prefix, voice='voice_arranged'):
-  notes = sorted(notes, key=lambda n: generator.model.fraction(n['onset']))
-  result = []
-  cursor = fractions.Fraction()
-
-  def rests(end):
-    nonlocal cursor
-    for duration, written in generator.accompaniment.written_durations(end - cursor):
-      result.append(generator.model.make_event(prefix + '_rest_' + str(len(result)), cursor, duration, 'rest', written=written) | {'voice': voice})
-      cursor += duration
-
-  for n in notes:
-    start = generator.model.fraction(n['onset'])
-    if start < cursor:
-      raise ValueError(prefix + ': overlapping independently generated roles')
-    rests(start)
-    n['voice'] = voice
-    result.append(n)
-    cursor = start + generator.model.fraction(n['duration'])
-  rests(length)
-  return result
-
-def generate_role(source, role, data_dir, settings=None, cache_dir=None):
-  started = time.monotonic()
-  with generator.input_audit.composition(data_dir, role, cache_dir) as reads:
-    result = _generate_role(source, role, data_dir, settings, cache_dir)
-  # Observed reads are diagnostics, never cache identity or musical seeds.
-  result['trace'] = {**result['trace'], 'input_boundary': 'production data (including explicit authored repertoire), generator code, Python runtime, own role cache'}
-  result['observed_reads'] = sorted(reads)
-  result['seconds'] = time.monotonic() - started
-  return result
-
-def _generate_role(source, role, data_dir, settings=None, cache_dir=None):
-  if role not in ROLES:
-    raise ValueError('Unknown generation role: ' + role)
-  data_dir = pathlib.Path(data_dir)
-  resources = generator.vocabulary.load(data_dir / 'composition')
-  settings = settings or {}
-  registered = generator.solo.authored.lookup(source, role.removesuffix('_solo'), data_dir) if role.endswith('_solo') and not settings.get('predict', False) else None
-  algorithm = VERSION + '/' + generator.solo.learned.VERSION if role.endswith('_solo') else VERSION
-  inputs = {'version': algorithm, 'source': source.musical_key, 'role': role, 'settings': settings,
-    'vocabulary': dependencies(role, resources, generator.score.source_staff(source.document())['measures']), 'catalogs': ({'authored': registered['sha256'], 'id': registered['id'], 'pitch_convention': registered['pitch_convention']} if registered else _resource_key(data_dir, role)), 'code': _code_key(role)}
-  # Source notation/lyrics also invalidate cached score representation, never the musical seed.
-  key = generator.vocabulary.fingerprint({'inputs': inputs, 'notation': source.document_json})
-  path = pathlib.Path(cache_dir) / role / (key + '.json') if cache_dir else None
-  if path and path.is_file() and not path.is_symlink():
-    try:
-      entry = json.loads(path.read_text())
-      value = entry['result']
-      if entry['key'] == key and entry['digest'] == generator.vocabulary.fingerprint(value):
-        generator.model.validate_document(value['document'])
-        generator.fretboard.validate_document(value['document'])
-        return {**value, 'cache_hit': True}
-    except (ValueError, KeyError, TypeError):
-      pass
-  started = time.monotonic()
-  document = source.document()
-  part = role.split('_')[0]
-  trace = {'source': source.musical_key, 'role': role, 'production_resources': inputs['catalogs'],
-    'vocabulary': generator.vocabulary.fingerprint(inputs['vocabulary']), 'settings': settings, 'algorithm': algorithm, 'code': inputs['code'], 'cache_key': key}
-  choice_source = source.accompaniment_key() if role.endswith('_accompaniment') else source.musical_key
-  choice_data, choice_settings = inputs['vocabulary'], settings
-  if role.endswith('_accompaniment'):
-    # Voicing weights invalidate the concrete cache, but must not reshuffle
-    # rhythm patterns. Removing this new field preserves the pre-policy seed.
-    choice_data = copy.deepcopy(choice_data)
-    choice_data['roles']['role'].pop('voicing', None)
-    for field in ('provenance', 'license', 'research'):
-      choice_data['accompaniment'].pop(field, None)
-    choice_settings = {k: v for k, v in settings.items() if k != 'voicing'}
-  seed = generator.vocabulary.fingerprint({'source': choice_source, 'role': role, 'settings': choice_settings, 'data': choice_data, 'version': algorithm})
-  details = {}
-  solo_report = ''
-  composition_timings = {}
-  with generator.vocabulary.using(resources, role, settings | {'choice_seed': seed}):
-    if role.endswith('_solo'):
-      result = generator.arrange.generate._arrange_document(document, part, {}, owned={'slash'})
-      si = 3 if part == 'acoustic' else 4
-      first, count, offset, length = generator.solo.arrangement.regions(document)[si]
-      # The template/harmony comes directly from source form, not another generated part.
-      authored = generator.score.source_staff(document)['measures']
-      section = generator.arrange.form.full_arrangement_sections(authored, part)[si]
-      effective = generator.arrange.generate.section_source(authored, section, generator.arrange.form.full_arrangement_sections(authored, part)[si + 1])
-      template = copy.deepcopy(effective[section.source_measure_index:section.source_measure_index + count])
-      initial = generator.accompaniment.carried_chords(effective)[section.source_measure_index]
-      start, end = next((a - offset, b - offset) for a, b, r in windows(document, part) if r == role)
-      notation_first = first
-      if start < 0:
-        # The preceding arrangement harmony comes from the source form. Do
-        # not invent harmony from a comparison score's unlabelled lead-in.
-        template.insert(0, copy.deepcopy(result['staves'][0]['measures'][first - 1]))
-        notation_first -= 1
-        initial = generator.accompaniment.carried_chords(result['staves'][0]['measures'])[first - 1]
-      if registered:
-        solo = generator.solo.authored.realize(registered, generator.solo.analysis.analyze(document), template, part, start, end, initial)
-      else:
-        solo_model = _solo_model(str(data_dir), inputs['catalogs']['model'])
-        solo = generator.solo.composer.compose(generator.solo.analysis.analyze(document), template, part, end, initial=initial, learned_model=solo_model, expressions_enabled=generator.vocabulary.role().get('expressions', True), start=start)
-      composition_timings = {k: v for k, v in solo.diagnostics.items() if k.endswith('_seconds')}
-      relative = tuple(dataclasses.replace(n, start=n.start - start, end=n.end - start) for n in solo.notes())
-      output = generator.solo.notation.measures(result['staves'][0]['measures'][notation_first:first + count], relative, 'solo_' + part)
-      generator.solo.notation.replace_region(result, notation_first, output)
-      details = generator.solo.report.structure(solo)
-      details['allocation'] = {'start': str(start), 'end': str(end), 'lead_in_measures': first - notation_first}
-      solo_report = generator.solo.report.describe(solo, first, offset, detail=details)
-    elif role.endswith('_accompaniment'):
-      canonical = generator.comping.Canonical(document, part, seed)
-      result = generator.arrange.generate._arrange_document(document, part, {}, owned={'accompaniment'}, accompaniment=canonical)
-      details = {'canonical_comping': canonical.report, 'accompaniment_rhythm': canonical.rhythm_report, 'groove_cycles': canonical.groove_report, 'rhythm_source': choice_source}
-    else:
-      result = generator.arrange.generate._arrange_document(document, part, {}, owned={'vocal' if part == 'vocal' else 'melody'})
-  allowed = tuple((a, b) for a, b, r in windows(document, part) if r == role)
-  _mask(result, allowed)
-  if role == "acoustic_accompaniment":
-    generator.acoustic.validate_comping(result)
-  staff = result['staves'][0]
-  for measure in staff['measures']:
-    measure['id'] = role + '_' + measure['id']
-  staff['tuplets'] = generator.score.reidentify(staff['measures'], staff.get('tuplets', []))
-  if part != 'vocal':
-    result['staves'][0]['tablature'] = True
-  generator.model.validate_document(result)
-  generator.fretboard.validate_document(result)
-  value = {'role': role, 'document': result, 'trace': trace, 'details': details, 'report': solo_report, 'seconds': time.monotonic() - started, 'composition_timings': composition_timings, 'cache_hit': False}
-  # Sidecar diagnostics use the same rational-safe representation as reports.
-  # Identical insertion order after cold generation and cache loading also
-  # keeps serialized scores and the catalog byte-for-byte reproducible.
-  value = json.loads(json.dumps(value, default=str, sort_keys=True))
-  if path:
-    path.parent.mkdir(parents=True, exist_ok=True)
-    payload = {'key': key, 'digest': generator.vocabulary.fingerprint(value), 'result': value}
-    with tempfile.NamedTemporaryFile('w', dir=path.parent, delete=False) as out:
-      json.dump(payload, out, sort_keys=True)
-      temporary = out.name
-    os.replace(temporary, path)
-  return value
-
-def assemble(source, results):
-  """Union prevalidated role windows; no selection or pitch/fingering rewrite."""
-  documents = {}
-  for part in generator.parts.PART_TYPES:
-    selected = [results[r]['document'] for r in ROLES if r.startswith(part + '_')]
-    document = copy.deepcopy(selected[0])
-    staff = document['staves'][0]
-    if part == 'vocal':
-      documents[part] = document
-      continue
-    staff['tuplets'] = []
-    staff['octave_shifts'] = []
-    staff['scale_spans'] = []
-    for other in selected:
-      for field in ('tuplets', 'octave_shifts', 'scale_spans'):
-        staff[field].extend(copy.deepcopy(other['staves'][0].get(field, [])))
-    for i, m in enumerate(staff['measures']):
-      # Tuplet rests belong to the source/role rhythm and must survive union.
-      lanes = {}
-      for d in selected:
-        for voice in d['staves'][0]['measures'][i]['voices']:
-          lane = voice['id'] if part == 'acoustic' and voice['id'] in ('upper', 'bass') else 'voice_arranged'
-          sounding = [copy.deepcopy(n) for n in voice['notes'] if n['pitches'] or n.get('tuplet_ids')]
-          if sounding:
-            lanes.setdefault(lane, []).extend(sounding)
-      lanes = lanes or {'voice_arranged': []}
-      m['voices'] = [{'id': lane, 'notes': _fill(notes, generator.model.fraction(m['duration']), m['id'] + '_' + lane, lane)} for lane, notes in lanes.items()]
-      # Attribute changes belong to source melody pickups and are assembly metadata.
-      for d in selected:
-        other = d['staves'][0]['measures'][i]
-        if other.get('attributes'):
-          m['attributes'] = copy.deepcopy(other['attributes'])
-    staff['tuplets'] = generator.arrange.pickup.retain_links(staff['measures'], staff['tuplets'])
-    owners = {n['id']: v['id'] for m in staff['measures'] for v in m['voices'] for n in v['notes']}
-    for span in staff['tuplets']:
-      span['voice'] = owners[span['start']]
-    generator.model.validate_document(document)
-    generator.fretboard.validate_document(document)
-    documents[part] = document
-  return documents
+import generator.score_io
+import generator.source
 
 def _job(request):
-  source, role, directory, settings, cache = request
-  return generate_role(source, role, directory, settings, cache)
+  return generator.composition.generate_role(request.source, request.role, request.directory, json.loads(request.settings_json), request.cache)
 
 def generate_tree(source_dir, output_dir, *, jobs=2, cache_dir=None, progress=False, timings=None):
   if type(jobs) is not int or not 1 <= jobs <= 16:
@@ -345,8 +26,8 @@ def generate_tree(source_dir, output_dir, *, jobs=2, cache_dir=None, progress=Fa
   sources = {}
   for path in generator.parts.source_paths(source_dir):
     document = generator.parts.prepare_document(generator.musicxml.load_musicxml(path))
-    sources[path] = (document, SourceAnalysis.read(document))
-  requests = [(path, role, (s, role, source_dir.parent, {}, cache_dir)) for path, (_, s) in sources.items() for role in ROLES]
+    sources[path] = (document, generator.source.SourceAnalysis.read(document))
+  requests = [(path, role, generator.composition_types.RoleRequest(s, role, source_dir.parent, cache=cache_dir)) for path, (_, s) in sources.items() for role in generator.composition_types.ROLES]
   results = {p: {} for p in sources}
 
   def accept(path, role, value):
@@ -372,16 +53,16 @@ def generate_tree(source_dir, output_dir, *, jobs=2, cache_dir=None, progress=Fa
         except Exception as error:
           raise ValueError(f'{path.name}/{role}: {error}') from error
   for path, (original, source) in sources.items():
-    assembled = assemble(source, results[path])
+    assembled = generator.arrange.assembly.assemble(source, results[path])
     generator.arrange.accompaniment.audit(original, assembled)
     reuse = generator.arrange.accompaniment.audit(original, {role: value['document'] for role, value in results[path].items()}, role_documents=True)
     for part, document in assembled.items():
       document['metadata'] = copy.deepcopy(original['metadata'])
       document['metadata']['song_id'] = generator.score.slugify(path.stem)
-      generator.score.write_json(output_dir / (generator.score.slugify(path.stem) + '_' + part + '.json'), document)
+      generator.score_io.write_json(output_dir / (generator.score.slugify(path.stem) + '_' + part + '.json'), document)
     analysis_dir = output_dir.parent / 'analysis'
     analysis_dir.mkdir(parents=True, exist_ok=True)
-    (analysis_dir / (generator.score.slugify(path.stem) + '.txt')).write_text('\n'.join(results[path][r]['report'] for r in ROLES))
+    (analysis_dir / (generator.score.slugify(path.stem) + '.txt')).write_text('\n'.join(results[path][r]['report'] for r in generator.composition_types.ROLES))
     # Not a score file: diagnostics are deliberately outside the songs schema.
     stable = {role: {k: v for k, v in value.items() if k not in ('seconds', 'composition_timings', 'cache_hit', 'observed_reads')} for role, value in results[path].items()}
     for role, audit in reuse.items():
diff --git a/generator/role_cache.py b/generator/role_cache.py
new file mode 100644
index 0000000..4ed6e9f
--- /dev/null
+++ b/generator/role_cache.py
@@ -0,0 +1,29 @@
+"""Role cache persistence; cache identity never supplies musical randomness."""
+import json
+
+import generator.cache
+import generator.fretboard
+import generator.validation
+
+ENTRYPOINTS = ('generator.composition',)
+
+def code_key():
+  return generator.cache.fingerprint(generator.cache.source_identity(ENTRYPOINTS))
+
+def restore(path, key):
+  if path is None or not path.is_file() or path.is_symlink():
+    return None
+  try:
+    entry = json.loads(path.read_text())
+    value = entry['result']
+    if entry['key'] == key and entry['digest'] == generator.cache.fingerprint(value):
+      generator.validation.validate_document(value['document'])
+      generator.fretboard.validate_document(value['document'])
+      return {**value, 'cache_hit': True}
+  except (OSError, ValueError, KeyError, TypeError):
+    pass
+  return None
+
+def store(path, key, value):
+  if path is not None:
+    generator.cache.write_json(path, {'key': key, 'digest': generator.cache.fingerprint(value), 'result': value})
diff --git a/generator/score.py b/generator/score.py
index dfc9377..9e0fd4e 100644
--- a/generator/score.py
+++ b/generator/score.py
@@ -1,53 +1,8 @@
+"""Pure score navigation, cloning and identity operations."""
 from __future__ import annotations
-
 import copy
-import json
-import pathlib
 import re
 
-import generator.engraving.validation
-import generator.fretboard
-import generator.model
-import generator.pico_artwork
-import generator.performance
-
-def load_json(path: pathlib.Path) -> dict:
-  document = json.loads(path.read_text(encoding='utf-8'))
-  return validate_json(document, path)
-
-def validate_json(document: dict, path: pathlib.Path, validated_pages: set[str] | None = None) -> dict:
-  if not isinstance(document, dict):
-    raise ValueError('expected a score object')
-  if 'music' in document:
-    presentation = document.get('presentation', {})
-    if not isinstance(document['music'], dict) or not isinstance(presentation, dict) or not isinstance(presentation.get('pages'), list) or not presentation['pages']:
-      raise ValueError('invalid score bundle; regenerate score assets')
-    if (presentation.get('engine'), presentation.get('width'), presentation.get('height')) != (generator.engraving.validation.ENGINE_NAME, generator.engraving.validation.PAGE_WIDTH, generator.engraving.validation.PAGE_HEIGHT):
-      raise ValueError('unsupported score presentation; regenerate score assets')
-    generator.performance.validate_views(document['music'], presentation['pages'], presentation.get('playback_pages'))
-    if document.get('performance') != generator.performance.timing(document['music']):
-      raise ValueError('invalid performance timing')
-    for page in presentation['pages'] + presentation['playback_pages']:
-      if not isinstance(page, dict) or not isinstance(page.get('path'), str) or not isinstance(page.get('sha256'), str):
-        raise ValueError('invalid score page manifest')
-      name = page['path']
-      relative = pathlib.Path(name)
-      if '\x00' in name or '\\' in name or relative.is_absolute() or any(part in ('', '.', '..') for part in name.split('/')) or relative.suffix != '.png':
-        raise ValueError('invalid score page path')
-      resolved = (path.parent / relative).resolve()
-      if not resolved.is_relative_to(path.parent.resolve()):
-        raise ValueError('score page escapes its asset directory')
-      generator.engraving.validation.check_page(resolved, validated_pages, expected_sha256=page['sha256'])
-    document = document['music']
-  generator.model.validate_document(document)
-  return document
-
-def write_json(path: pathlib.Path, document: dict) -> None:
-  generator.model.validate_document(document)
-  generator.fretboard.validate_document(document)
-  path.parent.mkdir(parents=True, exist_ok=True)
-  path.write_text(json.dumps(document, indent=2, ensure_ascii=False) + '\n', encoding='utf-8')
-
 def slugify(value: str) -> str:
   return re.sub(r'[^a-z0-9]+', '_', value.strip().lower()).strip('_') or 'score'
 
@@ -124,15 +79,3 @@ def reidentify(measures: list[dict], source_tuplets: list[dict]) -> list[dict]:
 
 def make_arranged_document(source_document: dict, staff: dict, *, staff_id: str, staff_name: str, role: str, arrangement_part_type: str, measures: list[dict], tuplets=None, octave_shifts=None) -> dict:
   return {'metadata': copy.deepcopy(source_document['metadata']), 'staves': [{'id': staff_id, 'name': staff_name, 'clef': copy.deepcopy(staff['clef']), 'role': role, 'arranged': True, 'arrangement_part_type': arrangement_part_type, 'measures': measures, 'tuplets': tuplets or [], 'octave_shifts': copy.deepcopy(octave_shifts or []), 'instruments': copy.deepcopy(staff.get('instruments', []))}]}
-
-def count_json_files(root: pathlib.Path) -> int:
-  return sum(1 for p in root.rglob('*.json') if p.is_file())
-
-def validate_generated_tree(root: pathlib.Path, validated_pages: set[str] | None = None) -> None:
-  validated_pages = set() if validated_pages is None else validated_pages
-  for path in root.rglob('*.json'):
-    document = json.loads(path.read_text(encoding='utf-8'))
-    music = validate_json(document, path, validated_pages)
-    generator.fretboard.validate_document(music)
-    if 'presentation' in document:
-      generator.pico_artwork.validate_title(root, document['presentation'].get('title_image'))
diff --git a/generator/score_io.py b/generator/score_io.py
new file mode 100644
index 0000000..05c605e
--- /dev/null
+++ b/generator/score_io.py
@@ -0,0 +1,59 @@
+from __future__ import annotations
+
+import json
+import pathlib
+
+import generator.engraving.validation
+import generator.fretboard
+import generator.performance
+import generator.pico_artwork
+import generator.validation
+
+def load_json(path: pathlib.Path) -> dict:
+  document = json.loads(path.read_text(encoding='utf-8'))
+  return validate_json(document, path)
+
+def validate_json(document: dict, path: pathlib.Path, validated_pages: set[str] | None = None) -> dict:
+  if not isinstance(document, dict):
+    raise ValueError('expected a score object')
+  if 'music' in document:
+    presentation = document.get('presentation', {})
+    if not isinstance(document['music'], dict) or not isinstance(presentation, dict) or not isinstance(presentation.get('pages'), list) or not presentation['pages']:
+      raise ValueError('invalid score bundle; regenerate score assets')
+    if (presentation.get('engine'), presentation.get('width'), presentation.get('height')) != (generator.engraving.validation.ENGINE_NAME, generator.engraving.validation.PAGE_WIDTH, generator.engraving.validation.PAGE_HEIGHT):
+      raise ValueError('unsupported score presentation; regenerate score assets')
+    generator.performance.validate_views(document['music'], presentation['pages'], presentation.get('playback_pages'))
+    if document.get('performance') != generator.performance.timing(document['music']):
+      raise ValueError('invalid performance timing')
+    for page in presentation['pages'] + presentation['playback_pages']:
+      if not isinstance(page, dict) or not isinstance(page.get('path'), str) or not isinstance(page.get('sha256'), str):
+        raise ValueError('invalid score page manifest')
+      name = page['path']
+      relative = pathlib.Path(name)
+      if '\x00' in name or '\\' in name or relative.is_absolute() or any(part in ('', '.', '..') for part in name.split('/')) or relative.suffix != '.png':
+        raise ValueError('invalid score page path')
+      resolved = (path.parent / relative).resolve()
+      if not resolved.is_relative_to(path.parent.resolve()):
+        raise ValueError('score page escapes its asset directory')
+      generator.engraving.validation.check_page(resolved, validated_pages, expected_sha256=page['sha256'])
+    document = document['music']
+  generator.validation.validate_document(document)
+  return document
+
+def write_json(path: pathlib.Path, document: dict) -> None:
+  generator.validation.validate_document(document)
+  generator.fretboard.validate_document(document)
+  path.parent.mkdir(parents=True, exist_ok=True)
+  path.write_text(json.dumps(document, indent=2, ensure_ascii=False) + '\n', encoding='utf-8')
+
+def count_json_files(root: pathlib.Path) -> int:
+  return sum(1 for p in root.rglob('*.json') if p.is_file())
+
+def validate_generated_tree(root: pathlib.Path, validated_pages: set[str] | None = None) -> None:
+  validated_pages = set() if validated_pages is None else validated_pages
+  for path in root.rglob('*.json'):
+    document = json.loads(path.read_text(encoding='utf-8'))
+    music = validate_json(document, path, validated_pages)
+    generator.fretboard.validate_document(music)
+    if 'presentation' in document:
+      generator.pico_artwork.validate_title(root, document['presentation'].get('title_image'))
diff --git a/generator/solo/authored.py b/generator/solo/authored.py
index efb7945..e8f6bfa 100644
--- a/generator/solo/authored.py
+++ b/generator/solo/authored.py
@@ -6,20 +6,21 @@ policy. Unknown song/role pairs go to the learned composer.
 """
 from __future__ import annotations
 import dataclasses
+import fractions
 import hashlib
 import json
 import pathlib
-import fractions
+
+import generator.harmonic_time
 import generator.musicxml
 import generator.parts
-import generator.training_io
-import generator.harmonic_time
-import generator.solo.analysis
-import generator.solo.types
+import generator.solo.harmonic
 import generator.solo.placement
 import generator.solo.profiles
-import generator.solo.harmonic
-import generator.production
+import generator.solo.types
+import generator.source
+import generator.training_io
+import generator.vocabulary
 
 def sounding(evidence, offset=fractions.Fraction()):
   result = []
@@ -32,9 +33,10 @@ def sounding(evidence, offset=fractions.Fraction()):
     result.append(generator.solo.types.Note(fractions.Fraction(event['start']) - offset, fractions.Fraction(event['end']) - offset, pitch, role='authored', event_id=f'authored_{i}'))
   return tuple(result)
 
-def validate_evidence(document, evidence):
+def validate_evidence(document, evidence, *, composition=None):
   """Training uses the same source-form harmonic context as solo playback."""
-  h = generator.solo.harmonic.Harmony(generator.harmonic_time.solo_source(document['staves'][0]))
+  composition = composition or generator.vocabulary.current()
+  h = generator.solo.harmonic.Harmony(generator.harmonic_time.solo_source(document['staves'][0]), composition=composition)
   checked = h.evaluate(sounding(evidence), complete=True)
   if not checked.valid:
     raise ValueError('Unsupported harmonic relationship in authored solo: ' + checked.error)
@@ -56,7 +58,7 @@ def lookup(source, role, data_dir):
     if not path.is_relative_to((root / 'songs').resolve()):
       raise ValueError('Registered sources must be in data/songs')
     doc = generator.parts.prepare_document(generator.musicxml.load_musicxml(path))
-    if generator.production.SourceAnalysis.read(doc).musical_key == source.musical_key:
+    if generator.source.SourceAnalysis.read(doc).musical_key == source.musical_key:
       target = (manifest.parent / entry['solo']).resolve()
       if not target.is_relative_to(manifest.parent.resolve()):
         raise ValueError('Registered solo must be inside data/training')
@@ -67,7 +69,8 @@ def lookup(source, role, data_dir):
     raise ValueError('Multiple authored solos registered for the same source music and role')
   return matches[0] if matches else None
 
-def realize(entry, source_analysis, measures, part, start, end, initial=None):
+def realize(entry, source_analysis, measures, part, start, end, initial=None, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   evidence = generator.training_io.read(entry['path'], part, pitch_convention=entry['pitch_convention'])
   if evidence['discrepancies']:
     raise ValueError(entry['id'] + ': invalid authored timing/ties: ' + str(evidence['discrepancies']))
@@ -86,7 +89,7 @@ def realize(entry, source_analysis, measures, part, start, end, initial=None):
   if placed is None:
     raise ValueError(entry['id'] + ': no legal complete guitar placement')
   spans = tuple(dataclasses.replace(s, start=s.start + start, end=s.end + start) for s in generator.harmonic_time.read({'measures': measures}, initial=initial))
-  checked = generator.solo.harmonic.Harmony(spans).evaluate(placed[1], complete=True)
+  checked = generator.solo.harmonic.Harmony(spans, composition=composition).evaluate(placed[1], complete=True)
   if not checked.valid:
     raise ValueError(entry['id'] + ': ' + checked.error)
   phrase = generator.solo.types.Phrase('authored', start, end, placed[1], 'authored', 'authored', 'handoff', theme=entry['id'], expressions=checked.contracts)
diff --git a/generator/solo/composer.py b/generator/solo/composer.py
index eaf3a62..2ecfec6 100644
--- a/generator/solo/composer.py
+++ b/generator/solo/composer.py
@@ -1,26 +1,28 @@
 """The sole production solo composer: frozen learned model plus music validity."""
 import dataclasses
-import time
 import fractions
 import pathlib
+import time
+
 import generator.harmonic_time
-import generator.vocabulary
-import generator.solo.types
-import generator.solo.profiles
-import generator.solo.harmonic
-import generator.solo.placement
-import generator.solo.learned
 import generator.solo.decoder
 import generator.solo.groups
+import generator.solo.harmonic
+import generator.solo.learned
+import generator.solo.placement
+import generator.solo.profiles
+import generator.solo.types
+import generator.vocabulary
 
-def compose(analysis, measures, part, end, *, learned_model=None, initial=None, expressions_enabled=True, start=fractions.Fraction()):
+def compose(analysis, measures, part, end, *, learned_model=None, initial=None, expressions_enabled=True, start=fractions.Fraction(), composition=None):
+  composition = composition or generator.vocabulary.current()
   began = time.monotonic()
   spans = tuple(dataclasses.replace(s, start=s.start + start, end=s.end + start) for s in generator.harmonic_time.read({'measures': measures}, initial=initial))
   profile = generator.solo.profiles.for_part(part, analysis)
-  harmony = generator.solo.harmonic.Harmony(spans, profile)
+  harmony = generator.solo.harmonic.Harmony(spans, profile, composition=composition)
   model = learned_model or generator.solo.learned.Model.load(pathlib.Path(__file__).resolve().parents[2] / 'data/models/solo.json')
-  settings = generator.vocabulary.role(part + '_solo')
-  builder = generator.solo.decoder.Decoder(analysis, harmony, model, part, start, end, expressions_enabled=expressions_enabled, attempts=settings.get('attempts', 4), seed=settings.get('choice_seed', ''))
+  settings = composition.role(part + '_solo')
+  builder = generator.solo.decoder.Decoder(analysis, harmony, model, part, start, end, expressions_enabled=expressions_enabled, attempts=settings.get('attempts', 4), seed=settings.get('choice_seed', ''), composition=composition)
   selected = builder.compose()
   decoded = time.monotonic()
   placed = generator.solo.placement.place(selected.notes, analysis.tempo, profile=profile)
@@ -48,10 +50,11 @@ def compose(analysis, measures, part, end, *, learned_model=None, initial=None,
       'counts': dict(builder.counts), 'frontiers': builder.trace, 'completed_candidates': [
         {'rank': i + 1, 'cost': s.cost, 'events': [(str(a), str(b), p) for a, b, p in s.events]} for i, s in enumerate(builder.completed)],
       'expressions_enabled': expressions_enabled}, profile, start)
-  validate(result)
+  validate(result, composition=composition)
   return result
 
-def validate(solo):
+def validate(solo, *, composition=None):
+  composition = composition or generator.vocabulary.current()
   previous = None
   for n in solo.notes():
     if n.start < solo.start or n.end > solo.end or n.end <= n.start or previous and previous.end > n.start:
@@ -59,7 +62,7 @@ def validate(solo):
     if n.position not in generator.solo.placement.positions(n.pitch.number(), solo.profile):
       raise ValueError('invalid guitar placement')
     previous = n
-  checked = generator.solo.harmonic.Harmony(solo.harmony).evaluate(solo.notes(), until=solo.end, complete=True,
+  checked = generator.solo.harmonic.Harmony(solo.harmony, composition=composition).evaluate(solo.notes(), until=solo.end, complete=True,
     expressions=tuple(c for p in solo.phrases for c in p.expressions))
   if not checked.valid:
     raise ValueError(checked.error)
diff --git a/generator/solo/decoder.py b/generator/solo/decoder.py
index b7f5efe..cea9f6a 100644
--- a/generator/solo/decoder.py
+++ b/generator/solo/decoder.py
@@ -8,17 +8,18 @@ legacy fallback. A bounded restart handles an exhausted/entirely silent sample.
 from __future__ import annotations
 import collections
 import dataclasses
-import hashlib
-import random
-import math
 import fractions
+import hashlib
+import math
+import random
+
+import generator.harmony
 import generator.model
-import generator.vocabulary
 import generator.solo.expressions
 import generator.solo.groups
 import generator.solo.learned
 import generator.solo.types
-import generator.harmony
+import generator.vocabulary
 
 class SearchExhausted(ValueError):
   pass
@@ -35,7 +36,8 @@ class State:
 def event_key(events): return tuple((a, b, -1 if p is None else p) for a, b, p in events)
 
 class Decoder:
-  def __init__(self, analysis, harmony, model, role, start, end, *, expressions_enabled=True, attempts=4, seed=''):
+  def __init__(self, analysis, harmony, model, role, start, end, *, expressions_enabled=True, attempts=4, seed='', composition=None):
+    self.composition = composition or generator.vocabulary.current()
     if type(attempts) is not int or not 1 <= attempts <= 16:
       raise ValueError('attempts must be between 1 and 16')
     self.analysis, self.harmony, self.model, self.role = analysis, harmony, model, role
@@ -45,7 +47,7 @@ class Decoder:
     self.seed = seed or hashlib.sha256(repr((source, role, generator.solo.learned.VERSION)).encode()).hexdigest()
     self.expressions_enabled = expressions_enabled
     self.low, self.high = harmony.profile.register
-    limits = generator.vocabulary.data('roles')['difficulty']
+    limits = self.composition.data('roles')['difficulty']
     self.durations = tuple(d for d in model.durations if 0 < d <= 4 and d.denominator in (1, 2, 4) and
       (d.denominator != 4 or analysis.tempo <= limits['sixteenth_max_bpm']))
     self.allow_triplets = analysis.tempo <= limits['triplet_max_bpm']
@@ -92,12 +94,12 @@ class Decoder:
     bases = []
     regions = [(None, n)]
     regions.extend((s.start, dataclasses.replace(n, start=s.start)) for s in self.harmony.spans
-      if n.start < s.start < n.end and s.start - n.start <= fractions.Fraction(generator.vocabulary.data('harmony')['anticipation_max']))
+      if n.start < s.start < n.end and s.start - n.start <= fractions.Fraction(self.composition.data('harmony')['anticipation_max']))
     for boundary, arrived in regions:
       exposed = [s for s, _, _ in self.harmony.segments(arrived) if n.pitch.number() % 12 not in s.roles.basic | s.roles.specified]
       if not exposed:
         continue
-      for rule in generator.vocabulary.data('harmony')['colors']:
+      for rule in self.composition.data('harmony')['colors']:
         if arrived.end - arrived.start > fractions.Fraction(rule['max_beats']):
           continue
         if any(s.chord == 'N.C.' or not generator.solo.expressions.eligible_color(rule, s, self.harmony) or
@@ -139,7 +141,7 @@ class Decoder:
       if self.harmony.evaluate((n,), complete=True, expressions=(c,), infer=False).valid:
         return tuple([c])
     for arriving in self.harmony.spans:
-      if n.start < arriving.start < n.end and arriving.start - n.start <= fractions.Fraction(generator.vocabulary.data('harmony')['anticipation_max']):
+      if n.start < arriving.start < n.end and arriving.start - n.start <= fractions.Fraction(self.composition.data('harmony')['anticipation_max']):
         c = generator.solo.types.ExpressionContract(n.event_id + ':anticipation', 'anticipation', 'early_chord_tone', (n,), n, arriving.chord, arriving.start)
         if self.harmony.evaluate((n,), complete=True, expressions=(c,), infer=False).valid:
           return tuple([c])
@@ -175,9 +177,9 @@ class Decoder:
     for rule, boundary in self.color_bases(n):
       if rule.get('resolve'):
         for gap in (fractions.Fraction(), fractions.Fraction(1, 2), fractions.Fraction(1)):
-          if gap <= fractions.Fraction(generator.vocabulary.data('harmony')['resolution_gap']):
+          if gap <= fractions.Fraction(self.composition.data('harmony')['resolution_gap']):
             requests.append(('color', rule, boundary, n.end + gap, (-2, -1, 1, 2)))
-    delay = generator.vocabulary.data('lead_ins')['delayed_approach']
+    delay = self.composition.data('lead_ins')['delayed_approach']
     if n.end - n.start <= fractions.Fraction(delay['max_note']) and n.pitch.number() % 12 not in self.harmony.permitted(n.start, n.end):
       for arrival in map(fractions.Fraction, delay['arrivals']):
         if n.end <= n.start + arrival <= n.start + fractions.Fraction(delay['deadline']):
@@ -219,7 +221,7 @@ class Decoder:
         if self.expressions_enabled and not self.harmony.ordinary(n):
           for events, ns, contracts in self.resolutions(n):
             add(events, ns, contracts)
-          rule = generator.vocabulary.data('lead_ins')['passing']
+          rule = self.composition.data('lead_ins')['passing']
           if duration <= fractions.Fraction(rule['max_note']):
             for step in rule['steps']:
               p = number + step
@@ -235,8 +237,8 @@ class Decoder:
                 c = generator.solo.types.ExpressionContract(n.event_id + ':passing', 'passing', rule['id'], (n,), target, self.harmony.at(end).chord)
                 add(((time, end, number), (end, end + hold, p)), (n, target), (c, *extra))
     if self.expressions_enabled:
-      limits = generator.vocabulary.data('roles')['difficulty']
-      for rule in generator.vocabulary.data('lead_ins')['patterns']:
+      limits = self.composition.data('roles')['difficulty']
+      for rule in self.composition.data('lead_ins')['patterns']:
         difficulty = rule.get('difficulty')
         if difficulty and self.analysis.tempo > limits[difficulty + '_max_bpm']:
           continue
@@ -313,9 +315,9 @@ class Decoder:
         return None
       contracts = tuple(dataclasses.replace(c, preparation=state.notes[-1]) if c.kind in ('connection', 'passing') and c.preparation is None else c for c in contracts)
       if self.harmony.ordinary(state.notes[-1]):
-        _, error = generator.solo.expressions.validate((state.notes[-1], *notes), contracts, self.harmony)
+        _, error = generator.solo.expressions.validate((state.notes[-1], *notes), contracts, self.harmony, composition=self.composition)
       else:
-        _, error = generator.solo.expressions.validate((*state.notes, *notes), (*state.contracts, *contracts), self.harmony)
+        _, error = generator.solo.expressions.validate((*state.notes, *notes), (*state.contracts, *contracts), self.harmony, composition=self.composition)
       if error:
         return None
     history = state.history
diff --git a/generator/solo/expressions.py b/generator/solo/expressions.py
index 118f237..51758c0 100644
--- a/generator/solo/expressions.py
+++ b/generator/solo/expressions.py
@@ -1,13 +1,14 @@
 """Typed, target-driven harmonic expression against written harmony and explicit musical relationships."""
 from __future__ import annotations
 import dataclasses
-import functools
 import fractions
+import functools
+
 import generator.harmony
 import generator.model
 import generator.pitch
-import generator.vocabulary
 import generator.solo.types
+import generator.vocabulary
 
 @functools.lru_cache(maxsize=512)
 def parsed_chord(symbol):
@@ -90,8 +91,9 @@ def _eligible_color(rule, span, harmony):
       return False
   return True
 
-def validate(notes, contracts, harmony):
+def validate(notes, contracts, harmony, *, composition=None):
   """Return event permissions only after checking complete actual gestures."""
+  composition = composition or generator.vocabulary.current()
   actual = {n.event_id: n for n in notes}
   approved = {}
 
@@ -115,7 +117,7 @@ def validate(notes, contracts, harmony):
       if not previous or previous.chord.strip('()') == span.chord.strip('()'):
         return {}, c.id + ': anticipation requires a harmonic change'
     if c.kind in ('approach', 'enclosure', 'connection'):
-      rule = next((r for r in generator.vocabulary.data('lead_ins')['patterns'] if r['id'] == c.rule and r['kind'] == c.kind), None)
+      rule = next((r for r in composition.data('lead_ins')['patterns'] if r['id'] == c.rule and r['kind'] == c.kind), None)
       if not rule or len(c.events) != len(rule['semitones']):
         return {}, c.id + ': unknown approach formula'
       arrival = c.boundary if c.boundary is not None else target.start
@@ -129,7 +131,7 @@ def validate(notes, contracts, harmony):
         return {}, c.id + ': invalid internal approach gaps'
       gap = fractions.Fraction(rule['gap'])
       cursor = target.start - gap - sum((fractions.Fraction(d) for d in rule['durations']), fractions.Fraction()) - sum(gaps, fractions.Fraction())
-      if target.start - cursor > fractions.Fraction(generator.vocabulary.data('lead_ins')['max_approach']):
+      if target.start - cursor > fractions.Fraction(composition.data('lead_ins')['max_approach']):
         return {}, c.id + ': approach too long'
       for i, (n, step, duration) in enumerate(zip(c.events, rule['semitones'], rule['durations'])):
         if n.start != cursor or n.end != cursor + fractions.Fraction(duration) or n.pitch.number() != target.pitch.number() + step:
@@ -144,7 +146,7 @@ def validate(notes, contracts, harmony):
       if c.kind == 'connection' and (not c.preparation or c.preparation.end != c.events[0].start or abs(c.preparation.pitch.number() - c.events[0].pitch.number()) > 2):
         return {}, c.id + ': chromatic connection lacks its incoming motion'
     elif c.kind == 'passing':
-      rule = generator.vocabulary.data('lead_ins')['passing']
+      rule = composition.data('lead_ins')['passing']
       if c.rule != rule['id'] or len(c.events) != 1 or not c.preparation:
         return {}, c.id + ': unsupported passing figure'
       n, = c.events
@@ -160,7 +162,7 @@ def validate(notes, contracts, harmony):
       if not supported(before) or not supported(target):
         return {}, c.id + ': unsupported passing endpoints'
     elif c.kind == 'delayed_approach':
-      rule = generator.vocabulary.data('lead_ins').get('delayed_approach', {})
+      rule = composition.data('lead_ins').get('delayed_approach', {})
       if c.rule != rule.get('id') or len(c.events) != 1:
         return {}, c.id + ': unknown delayed approach'
       n, = c.events
@@ -171,7 +173,7 @@ def validate(notes, contracts, harmony):
       if target.pitch.number() % 12 not in harmony.members(target.start, target.end) or target.pitch.number() % 12 not in harmony.permitted(target.start, target.end):
         return {}, c.id + ': invalid delayed destination'
     elif c.kind == 'color':
-      rule = next((r for r in generator.vocabulary.data('harmony')['colors'] if r['id'] == c.rule), None)
+      rule = next((r for r in composition.data('harmony')['colors'] if r['id'] == c.rule), None)
       if not rule:
         return {}, c.id + ': unknown color policy'
       colored = False
@@ -193,10 +195,10 @@ def validate(notes, contracts, harmony):
         return {}, c.id + ': no interval expresses the declared color'
       last = c.events[-1]
       if rule.get('resolve'):
-        if target.event_id == last.event_id or not 0 <= target.start - last.end <= fractions.Fraction(generator.vocabulary.data('harmony')['resolution_gap']) or not 0 < abs(target.pitch.number() - last.pitch.number()) <= 2 or target.pitch.number() % 12 not in harmony.members(target.start, target.end):
+        if target.event_id == last.event_id or not 0 <= target.start - last.end <= fractions.Fraction(composition.data('harmony')['resolution_gap']) or not 0 < abs(target.pitch.number() - last.pitch.number()) <= 2 or target.pitch.number() % 12 not in harmony.members(target.start, target.end):
           return {}, c.id + ': unresolved color'
     elif c.kind == 'suspension':
-      rule = next((r for r in generator.vocabulary.data('harmony').get('suspensions', []) if r['id'] == c.rule), None)
+      rule = next((r for r in composition.data('harmony').get('suspensions', []) if r['id'] == c.rule), None)
       if not rule or len(c.events) != 1 or c.boundary is None:
         return {}, c.id + ': unsupported suspension'
       held, = c.events
@@ -211,23 +213,23 @@ def validate(notes, contracts, harmony):
       if held.pitch.number() % 12 not in harmony.permitted(held.start, held.end):
         return {}, c.id + ': suspension outside source-key/chord motion'
     elif c.kind == 'anticipated_color':
-      rule = next((r for r in generator.vocabulary.data('harmony')['colors'] if r['id'] == c.rule), None)
+      rule = next((r for r in composition.data('harmony')['colors'] if r['id'] == c.rule), None)
       if not rule or len(c.events) != 1 or c.boundary != span.start:
         return {}, c.id + ': unsupported anticipated color'
       n, = c.events
-      if not n.start < c.boundary < n.end or c.boundary - n.start > fractions.Fraction(generator.vocabulary.data('harmony')['anticipation_max']):
+      if not n.start < c.boundary < n.end or c.boundary - n.start > fractions.Fraction(composition.data('harmony')['anticipation_max']):
         return {}, c.id + ': invalid anticipated color interval'
       arrived = dataclasses.replace(n, start=c.boundary)
       target = arrived if c.target == n else c.target
       inner = generator.solo.types.ExpressionContract(c.id + ':arrived', 'color', rule['id'], (arrived,), target, span.chord)
-      _, error = validate((arrived, *((target,) if target != arrived else ())), (inner,), harmony)
+      _, error = validate((arrived, *((target,) if target != arrived else ())), (inner,), harmony, composition=composition)
       if error:
         return {}, error
     elif c.kind == 'anticipation':
       if c.rule not in ('early_chord_tone', 'early_reattack') or len(c.events) != 1 or span.start != c.boundary:
         return {}, c.id + ': unknown anticipation or non-boundary target'
       n, = c.events
-      if c.boundary is None or not n.start < c.boundary or c.boundary - n.start > fractions.Fraction(generator.vocabulary.data('harmony')['anticipation_max']):
+      if c.boundary is None or not n.start < c.boundary or c.boundary - n.start > fractions.Fraction(composition.data('harmony')['anticipation_max']):
         return {}, c.id + ': invalid anticipation interval'
       if c.rule == 'early_chord_tone' and (n != target or not c.boundary < n.end):
         return {}, c.id + ': invalid held anticipation'
@@ -238,7 +240,7 @@ def validate(notes, contracts, harmony):
     elif c.kind == 'blues':
       if len(c.events) != 1:
         return {}, c.id + ': blues treatment requires one inflected event'
-      rule = next((r for r in generator.vocabulary.data('lead_ins')['blues'] if r['id'] == c.rule), None)
+      rule = next((r for r in composition.data('lead_ins')['blues'] if r['id'] == c.rule), None)
       n, = c.events
       chord = parsed_chord(span.chord)
       if not rule or n.end - n.start > fractions.Fraction(1, 2) or n.end != target.start or target.pitch.number() % 12 not in span.roles.basic:
@@ -262,15 +264,16 @@ def validate(notes, contracts, harmony):
       approved[n.event_id] = c
   return approved, ''
 
-def validate_frontier(notes, contracts, harmony, until, complete):
+def validate_frontier(notes, contracts, harmony, until, complete, *, composition=None):
   """Validate heard prefixes and bounded future obligations separately.
 
   Future contract events are used ONLY to establish rule feasibility. They do
   not count as heard resolution; the contract stays pending until its entire
   target hold is present. Missing past events and expired deadlines fail.
   """
+  composition = composition or generator.vocabulary.current()
   if complete:
-    approved, error = validate(notes, contracts, harmony)
+    approved, error = validate(notes, contracts, harmony, composition=composition)
     return approved, (), error
   actual = {n.event_id: n for n in notes}
   future = dict(actual)
@@ -290,5 +293,5 @@ def validate_frontier(notes, contracts, harmony, until, complete):
         return {}, (), c.id + ': missing/changed event before resolution deadline'
     if incomplete:
       pending.append(c)
-  approved, error = validate(tuple(sorted(future.values(), key=lambda n: (n.start, n.event_id))), contracts, harmony)
+  approved, error = validate(tuple(sorted(future.values(), key=lambda n: (n.start, n.event_id))), contracts, harmony, composition=composition)
   return {key: c for key, c in approved.items() if key in actual}, tuple(pending), error
diff --git a/generator/solo/harmonic.py b/generator/solo/harmonic.py
index 5e71c4a..0581304 100644
--- a/generator/solo/harmonic.py
+++ b/generator/solo/harmonic.py
@@ -5,14 +5,16 @@ permission follows the actual sounded interval and validated resolution.
 """
 from __future__ import annotations
 import dataclasses
-import functools
 import fractions
+import functools
+
 import generator.harmony
 import generator.model
-import generator.solo.types
-import generator.solo.profiles
 import generator.solo.expressions
+import generator.solo.profiles
 import generator.solo.recognition
+import generator.solo.types
+import generator.vocabulary
 
 @dataclasses.dataclass(frozen=True)
 class Roles:
@@ -55,7 +57,8 @@ class Result:
   contracts: tuple = ()
 
 class Harmony:
-  def __init__(self, spans, profile=None):
+  def __init__(self, spans, profile=None, *, composition=None):
+    self.composition = composition or generator.vocabulary.current()
     self.profile = profile or generator.solo.profiles.UNRESTRICTED
     self.source_spans = spans
     self.spans = []
@@ -112,14 +115,14 @@ class Harmony:
     expressions = tuple(dataclasses.replace(c, events=tuple(self.identified(n) for n in c.events),
       target=self.identified(c.target), preparation=self.identified(c.preparation) if c.preparation else None) for c in expressions)
     frontier = until if until is not None else max((n.end for n in notes), default=fractions.Fraction())
-    permissions, pending, error = generator.solo.expressions.validate_frontier(notes, expressions, self, frontier, complete or until is None)
+    permissions, pending, error = generator.solo.expressions.validate_frontier(notes, expressions, self, frontier, complete or until is None, composition=self.composition)
     if error:
       return Result(False, 0, error=error)
     if infer and not pending and (complete or until is None) and any(not self.ordinary(n) and n.event_id not in permissions for n in notes):
-      expressions, error = generator.solo.recognition.recognize(notes, self, expressions)
+      expressions, error = generator.solo.recognition.recognize(notes, self, expressions, composition=self.composition)
       if error:
         return Result(False, 0, error=error)
-      permissions, pending, error = generator.solo.expressions.validate_frontier(notes, expressions, self, frontier, True)
+      permissions, pending, error = generator.solo.expressions.validate_frontier(notes, expressions, self, frontier, True, composition=self.composition)
       if error:
         return Result(False, 0, error=error)
     exposed = sounded = fractions.Fraction()
diff --git a/generator/solo/profiles.py b/generator/solo/profiles.py
index 551b350..2391e0d 100644
--- a/generator/solo/profiles.py
+++ b/generator/solo/profiles.py
@@ -2,11 +2,10 @@
 from __future__ import annotations
 
 import dataclasses
-import functools
 import fractions
+import functools
 
 import generator.fretboard
-import generator.vocabulary
 
 @dataclasses.dataclass(frozen=True)
 class Instrument:
diff --git a/generator/solo/recognition.py b/generator/solo/recognition.py
index 36997a7..60d3d45 100644
--- a/generator/solo/recognition.py
+++ b/generator/solo/recognition.py
@@ -5,9 +5,10 @@ Existing expression validators prove each candidate; deterministic set-cover
 search chooses a mutually consistent explanation, never edits the notes.
 """
 import fractions
-import generator.vocabulary
+
 import generator.solo.expressions
 import generator.solo.types
+import generator.vocabulary
 
 def signature(c):
   return (c.kind, c.rule, tuple(n.event_id for n in c.events), c.target.event_id,
@@ -20,7 +21,8 @@ def merge(*groups):
       result.setdefault(signature(c), c)
   return tuple(result.values())
 
-def recognize(notes, harmony, provided=(), *, budget=4096):
+def recognize(notes, harmony, provided=(), *, budget=4096, composition=None):
+  composition = composition or generator.vocabulary.current()
   required = {n.event_id for n in notes if not harmony.ordinary(n)}
   fixed = {n.event_id for c in provided for n in c.events}
   if required <= fixed:
@@ -46,7 +48,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
     if not (covered & required):
       return False
     combined = merge(provided, bundle)
-    _, error = generator.solo.expressions.validate(notes, combined, harmony)
+    _, error = generator.solo.expressions.validate(notes, combined, harmony, composition=composition)
     if error:
       return False
     candidates[tuple(signature(a) for a in bundle)] = (bundle, covered)
@@ -57,11 +59,11 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
   for i, n in enumerate(notes):
     if n.event_id not in required:
       continue
-    future = [t for t in notes[i + 1:] if n.end <= t.start <= n.end + fractions.Fraction(generator.vocabulary.data('harmony')['resolution_gap'])
+    future = [t for t in notes[i + 1:] if n.end <= t.start <= n.end + fractions.Fraction(composition.data('harmony')['resolution_gap'])
       and 0 < abs(t.pitch.number() - n.pitch.number()) <= 2]
     regions = [(None, harmony.at(n.start))]
     regions.extend((s.start, s) for s in harmony.spans if n.start < s.start < n.end
-      and s.start - n.start <= fractions.Fraction(generator.vocabulary.data('harmony')['anticipation_max']))
+      and s.start - n.start <= fractions.Fraction(composition.data('harmony')['anticipation_max']))
     for boundary, span in regions:
       if not span or span.chord == 'N.C.':
         continue
@@ -69,7 +71,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
         c = contract('anticipation', 'early_chord_tone', (n,), n, boundary)
         if add(c):
           single.setdefault(n.event_id, []).append((c,))
-      for rule in generator.vocabulary.data('harmony')['colors']:
+      for rule in composition.data('harmony')['colors']:
         if not generator.solo.expressions.eligible_color(rule, span, harmony) and boundary is not None:
           continue
         kind = 'anticipated_color' if boundary is not None else 'color'
@@ -85,7 +87,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
       target = notes[i + 1]
       for s in harmony.spans:
         if n.start < s.start < n.end:
-          for rule in generator.vocabulary.data('harmony').get('suspensions', []):
+          for rule in composition.data('harmony').get('suspensions', []):
             add(contract('suspension', rule['id'], (n,), target, s.start))
         elif s.start == n.end == target.start and n.pitch.number() == target.pitch.number():
           add(contract('anticipation', 'early_reattack', (n,), target, s.start))
@@ -99,7 +101,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
         targets.append((None, support))
       elif c.kind == 'anticipation':
         targets.append((c.boundary, support))
-    for rule in generator.vocabulary.data('lead_ins')['patterns']:
+    for rule in composition.data('lead_ins')['patterns']:
       size = len(rule['semitones'])
       if i < size:
         continue
@@ -113,7 +115,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
         add(contract(rule['kind'], rule['id'], ns, target, boundary, preparation), extras)
     # Delayed approaches may include real space or intervening valid music.
     # They still have an exact semitone target and a finite deadline.
-    rule = generator.vocabulary.data('lead_ins')['delayed_approach']
+    rule = composition.data('lead_ins')['delayed_approach']
     for n in reversed(notes[:i]):
       if target.start - n.start > fractions.Fraction(rule['deadline']):
         break
@@ -124,8 +126,8 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
       if n.event_id in required:
         for left in [(), *single.get(before.event_id, ())]:
           for right in [(), *single.get(target.event_id, ())]:
-            add(contract('passing', generator.vocabulary.data('lead_ins')['passing']['id'], (n,), target, preparation=before), merge(left, right))
-        for rule in generator.vocabulary.data('lead_ins')['blues']:
+            add(contract('passing', composition.data('lead_ins')['passing']['id'], (n,), target, preparation=before), merge(left, right))
+        for rule in composition.data('lead_ins')['blues']:
           add(contract('blues', rule['id'], (n,), target, preparation=before))
   options = {identifier: [] for identifier in sorted(required - fixed, key=lambda identifier: (by_id[identifier].start, identifier))}
   for bundle, covered in candidates.values():
@@ -152,7 +154,7 @@ def recognize(notes, harmony, provided=(), *, budget=4096):
     identifier = min(remaining, key=lambda x: (len(options[x]), by_id[x].start, x))
     for bundle, added in options[identifier]:
       combined = merge(chosen, bundle)
-      _, error = generator.solo.expressions.validate(notes, combined, harmony)
+      _, error = generator.solo.expressions.validate(notes, combined, harmony, composition=composition)
       if error:
         continue
       result = solve(combined, covered | added)
diff --git a/generator/solo/report.py b/generator/solo/report.py
index 2f14193..4922cb8 100644
--- a/generator/solo/report.py
+++ b/generator/solo/report.py
@@ -1,9 +1,10 @@
 """Compact reports of actual selected phrases, not duplicated draft ancestry."""
-import dataclasses, fractions, json
-import generator.solo.placement
-import generator.solo.harmonic
 import collections
-import generator.fretboard
+import dataclasses, fractions, json
+
+import generator.solo.harmonic
+import generator.solo.placement
+import generator.vocabulary
 
 def plain(value):
   if dataclasses.is_dataclass(value):
@@ -16,8 +17,9 @@ def plain(value):
     return str(value)
   return value
 
-def structure(solo):
-  harmony = generator.solo.harmonic.Harmony(solo.harmony)
+def structure(solo, *, composition=None):
+  composition = composition or generator.vocabulary.current()
+  harmony = generator.solo.harmonic.Harmony(solo.harmony, composition=composition)
   contracts = tuple(c for p in solo.phrases for c in p.expressions)
   checked = harmony.evaluate(solo.notes(), until=solo.end, complete=True, expressions=contracts)
   phrases = []
@@ -37,8 +39,9 @@ def structure(solo):
     'harmonic_roles': harmony.describe(ns, expressions=contracts), 'harmonic_policy': 'contextual (shared by authored and predicted music)', 'harmonic_valid': checked.valid, 'harmonic_error': checked.error,
     'harmonic_exposure': checked.exposure, 'unresolved_treatments': plain(checked.pending)}
 
-def describe(solo, measure_offset=0, time_offset=0, *, detail=None):
-  detail = detail or structure(solo)
+def describe(solo, measure_offset=0, time_offset=0, *, detail=None, composition=None):
+  composition = composition or generator.vocabulary.current()
+  detail = detail or structure(solo, composition=composition)
   lines = [f'{solo.diagnostics.get("construction", "solo")}: {solo.part}', 'Times are exact quarter beats from the chorus start; negative times are allocated lead-ins. Pitches sound one octave below guitar notation.',
     'Approximate fingering costs are not a biomechanical guarantee.', json.dumps(detail['phrasing'])]
   for p in solo.phrases:
diff --git a/generator/solo/analysis.py b/generator/source.py
similarity index 56%
rename from generator/solo/analysis.py
rename to generator/source.py
index 5a5a868..777c282 100644
--- a/generator/solo/analysis.py
+++ b/generator/source.py
@@ -1,7 +1,14 @@
 """Immutable source events, meter boundaries and tempo. No solo construction."""
 from __future__ import annotations
-import dataclasses, fractions
-import generator.model, generator.score, generator.solo.types
+import copy
+import dataclasses
+import fractions
+import hashlib
+import json
+
+import generator.model
+import generator.score
+import generator.solo.types
 
 @dataclasses.dataclass(frozen=True)
 class Analysis:
@@ -43,3 +50,32 @@ def analyze(document):
     boundaries.append(boundaries[-1] + generator.model.fraction(m['duration']))
   tempo = next((generator.model.fraction(t['bpm']) * generator.model.written_length(t['written']) for m in measures for t in m.get('tempos', []) if 'bpm' in t), fractions.Fraction(120))
   return Analysis(tuple(boundaries), tempo, attacks(document), boundaries[generator.score.body_start_measure_index(measures)])
+
+@dataclasses.dataclass(frozen=True)
+class SourceAnalysis:
+  document_json: str
+  musical_key: str
+  @classmethod
+  def read(cls, document):
+    prepared = copy.deepcopy(document)
+    staff = generator.score.source_staff(prepared)
+    for i, m in enumerate(staff['measures']):
+      m['id'], m['number'] = f'source_{i}', str(i + 1)
+    staff['tuplets'] = generator.score.reidentify(staff['measures'], staff.get('tuplets', []))
+    prepared['metadata'] = {k: v for k, v in prepared['metadata'].items() if k not in ('title', 'composer', 'copyright', 'software')}
+    prepared['metadata'].update(title='Source', composer='')
+    staff.update(id='source', name='Source')
+    melodic = analyze(prepared)
+    content = {'melody': [(str(n.start), str(n.end), dataclasses.asdict(n.pitch)) for n in melodic.melody],
+      'measures': [{k: m.get(k) for k in ('duration', 'time_signature', 'key', 'harmonies', 'tempos', 'section_label', 'implicit')} for m in staff['measures']]}
+    # Fraction/string spelling is canonical and never includes filesystem IDs.
+    key = hashlib.sha256(json.dumps(content, sort_keys=True, default=str).encode()).hexdigest()
+    return cls(json.dumps(prepared, sort_keys=True), key)
+  def document(self):
+    return json.loads(self.document_json)
+  def accompaniment_key(self):
+    document = self.document()
+    document['metadata'].pop('tempo', None)
+    for measure in generator.score.source_staff(document)['measures']:
+      measure['tempos'] = []
+    return SourceAnalysis.read(document).musical_key
diff --git a/generator/summary.py b/generator/summary.py
index c291aca..205d88c 100644
--- a/generator/summary.py
+++ b/generator/summary.py
@@ -6,6 +6,7 @@ import typing
 
 import generator.model
 import generator.score
+import generator.score_io
 
 def _arranged_staff(document: dict[str, typing.Any]) -> dict[str, typing.Any]:
   staves = document.get("staves")
@@ -61,7 +62,7 @@ def performance_document_summary(document: dict[str, typing.Any]) -> dict[str, t
 
 def performance_tree_summary(root: pathlib.Path) -> dict[str, typing.Any]:
   return {
-    path.name: performance_document_summary(generator.score.load_json(path))
+    path.name: performance_document_summary(generator.score_io.load_json(path))
     for path in sorted(root.glob("*.json"))
   }
 
diff --git a/generator/train.py b/generator/train.py
index 2be328a..bf6ed90 100644
--- a/generator/train.py
+++ b/generator/train.py
@@ -3,26 +3,25 @@ from __future__ import annotations
 import argparse
 import collections
 import dataclasses
+import fractions
 import hashlib
 import json
 import os
 import pathlib
+import shutil
 import tempfile
 import time
-import fractions
+
+import generator.fretboard
+import generator.harmonic_time
 import generator.harmony
-import generator.model
 import generator.musicxml
 import generator.parts
+import generator.solo.authored
+import generator.solo.learned
+import generator.source
 import generator.training_io
 import generator.vocabulary
-import generator.harmonic_time
-import generator.solo.analysis
-import generator.solo.learned
-import shutil
-import generator.production
-import generator.solo.authored
-import generator.fretboard
 
 @dataclasses.dataclass(frozen=True)
 class Span:
@@ -57,8 +56,8 @@ def load_examples(manifest):
     if not source.is_relative_to((manifest.parent.parent / 'songs').resolve()):
       raise ValueError('Training sources must be inside data/songs')
     document = generator.parts.prepare_document(generator.musicxml.load_musicxml(source))
-    a = generator.solo.analysis.analyze(document)
-    pair = (generator.production.SourceAnalysis.read(document).musical_key, entry['slot'])
+    a = generator.source.analyze(document)
+    pair = (generator.source.SourceAnalysis.read(document).musical_key, entry['slot'])
     if pair in pairs:
       raise ValueError('Duplicate source music and solo slot')
     pairs.add(pair)
diff --git a/generator/validation.py b/generator/validation.py
new file mode 100644
index 0000000..11244df
--- /dev/null
+++ b/generator/validation.py
@@ -0,0 +1,161 @@
+"""Score document validation, above pure musical values and instrument rules."""
+from __future__ import annotations
+import fractions
+
+import generator.fretboard
+import generator.model
+import generator.pitch
+
+def validate_document(document: dict) -> None:
+  if not isinstance(document, dict) or not isinstance(document.get('metadata'), dict):
+    raise ValueError('score requires a metadata object')
+  if any(not isinstance(document['metadata'].get(name), str) for name in ('title', 'composer', 'key_signature', 'time_signature')):
+    raise ValueError('score metadata requires title, composer, key_signature and time_signature strings')
+  staves = document.get('staves', [])
+  if not isinstance(staves, list) or len(staves) != 1 or not isinstance(staves[0], dict):
+    raise ValueError('exactly one staff is currently supported')
+  if not isinstance(staves[0].get('measures'), list) or not staves[0]['measures']:
+    raise ValueError('score requires measures')
+  instruments = staves[0].get('instruments', [])
+  instrument_ids = {i['id'] for i in instruments}
+  if len(instruments) != len(instrument_ids) or any(not isinstance(i, str) or not i for i in instrument_ids):
+    raise ValueError('score instruments require unique nonempty IDs')
+  ids: set[str] = set()
+  events: dict[str, dict] = {}
+  tones: dict[str, tuple[dict, fractions.Fraction, fractions.Fraction, str]] = {}
+  ownership: dict[str, str] = {}
+  absolute = fractions.Fraction()
+  for measure in staves[0]['measures']:
+    if {'repeats', 'endings', 'initial_attributes'} & measure.keys():
+      raise ValueError('repeat notation is unsupported; regenerate scores from music written out in reading order')
+    length = generator.model.fraction(measure['duration'])
+    if length <= 0:
+      raise ValueError('measure duration must be positive')
+    voices = measure.get('voices', [])
+    if not voices or len({v['id'] for v in voices}) != len(voices) or any(not v['id'] for v in voices):
+      raise ValueError('measure requires uniquely identified voice lanes')
+    previous_ends = {v['id']: fractions.Fraction() for v in voices}
+    for voice, note in ((v, n) for v in voices for n in v['notes']):
+      if any({'sound_ties', 'printed_ties'} & pitch.keys() for pitch in note['pitches']):
+        raise ValueError('pass-specific tie metadata is unsupported; regenerate scores')
+      if not note['id'] or note['id'] in ids:
+        raise ValueError(f'duplicate event ID: {note["id"]}')
+      ids.add(note['id'])
+      events[note['id']] = note
+      ownership[note['id']] = voice['id']
+      if note.get('voice', voice['id']) != voice['id']:
+        raise ValueError('event voice ownership disagrees with its lane')
+      onset, duration = generator.model.fraction(note['onset']), generator.model.fraction(note['duration'])
+      if onset < 0 or duration < 0 or onset + duration > length:
+        raise ValueError(f'event outside measure: {note["id"]}')
+      if note['kind'] not in ('note', 'rest', 'spacer'):
+        raise ValueError('invalid event kind')
+      if not note.get('grace'):
+        if duration == 0 or onset < previous_ends[voice['id']]:
+          raise ValueError('overlapping events in one rhythmic voice')
+        previous_ends[voice['id']] = onset + duration
+      elif duration != 0:
+        raise ValueError('grace notes must not advance metric time')
+      expected = generator.model.metric_length(note['written'])
+      if not note.get('grace') and not note.get('measure_rest') and duration != expected:
+        raise ValueError('metric and written event durations disagree')
+      if note['kind'] != 'note' and note.get('pitches'):
+        raise ValueError('rests and spacers cannot contain pitches')
+      if note['kind'] == 'note' and not note.get('pitches') and note.get('notehead') != 'slash':
+        raise ValueError('pitched event requires at least one pitch')
+      for p in note.get('pitches', []):
+        if p.get('instrument') and p['instrument'] not in instrument_ids:
+          raise ValueError('note refers to an unknown score instrument')
+        if 'unpitched' in p:
+          position = p['unpitched']
+          if position['letter'] not in generator.model.LETTERS or type(position['octave']) is not int:
+            raise ValueError('invalid unpitched display position')
+        else:
+          generator.model.pitch_number(p)
+        if staves[0].get('tablature'):
+          tab = p.get('tablature', {})
+          string, fret = tab.get('string'), tab.get('fret')
+          if type(string) is not int or type(fret) is not int or string not in dict(generator.fretboard.STANDARD_TUNING) or not generator.fretboard.MIN_FRET <= fret <= generator.fretboard.MAX_FRET:
+            raise ValueError(f'{p["id"]}: invalid generated tablature position')
+          state = dict(measure)
+          for change in measure.get('attributes', []):
+            if generator.model.fraction(change['onset']) <= onset:
+              state.update(change)
+          if dict(generator.fretboard.STANDARD_TUNING)[string] + fret != generator.pitch.sounding_pitch(p, state):
+            raise ValueError(f'{p["id"]}: tablature disagrees with sounding pitch')
+        pd = generator.model.fraction(p['duration'])
+        if pd < 0 or (pd == 0 and not note.get('grace')) or pd > duration or not p['id'] or p['id'] in tones:
+          raise ValueError('invalid chord-tone duration or duplicate ID')
+        if not note.get('grace') and pd != generator.model.metric_length(p['written']):
+          raise ValueError('metric and written chord-tone durations disagree')
+        tones[p['id']] = (p, absolute + onset, pd, voice['id'])
+    for harmony in measure.get('harmonies', []):
+      if not 0 <= generator.model.fraction(harmony['onset']) < length:
+        raise ValueError('harmony outside measure')
+    for change in measure.get('attributes', []):
+      if not 0 <= generator.model.fraction(change['onset']) < length:
+        raise ValueError('attribute change outside measure')
+    for state in [measure, *measure.get('attributes', [])]:
+      if 'meter' in state:
+        generator.model.validate_meter(state['meter'])
+      if 'key' in state:
+        if len(state['key']['alterations']) != 7:
+          raise ValueError('key alterations must contain seven exact alterations')
+        for value in state['key']['alterations']:
+          generator.model.alteration(value)
+      if 'clef' in state and (state['clef']['sign'] not in ('G', 'F', 'C', 'percussion', 'none') or not 1 <= state['clef']['line'] <= 6 or not -3 <= state['clef']['octave_change'] <= 3):
+        raise ValueError('invalid clef')
+    absolute += length
+  for identifier, (p, start, duration, voice) in tones.items():
+    if target := p.get('tie_to'):
+      if target not in tones:
+        raise ValueError(f'dangling tie: {identifier} -> {target}')
+      other, next_start, _, next_voice = tones[target]
+      same_pitch = all(p.get(k) == other.get(k) for k in ('unpitched', 'instrument')) if 'unpitched' in p else all(p.get(k) == other.get(k) for k in ('letter', 'alter', 'octave'))
+      if other.get('tie_from') != identifier or not same_pitch or next_voice != voice or next_start != start + duration:
+        raise ValueError(f'invalid tie: {identifier} -> {target}')
+      if staves[0].get('tablature') and p['tablature'] != other['tablature']:
+        raise ValueError(f'{identifier}: tied guitar tones must retain their string and fret')
+    if source := p.get('tie_from'):
+      if source not in tones or tones[source][0].get('tie_to') != identifier:
+        raise ValueError(f'dangling incoming tie: {identifier}')
+  span_ids = set()
+  event_order = {identifier: index for index, identifier in enumerate(events)}
+  for span in staves[0].get('tuplets', []):
+    if not span['id'] or span['id'] in span_ids or span['start'] not in ids or span['end'] not in ids or not 0 < span['note_count'] <= 1000000 or not 0 < span['space_count'] <= 1000000 or not 0 <= span['depth'] <= 16:
+      raise ValueError('invalid tuplet span')
+    members = [n['id'] for n in events.values() if span['id'] in n.get('tuplet_ids', [])]
+    if not members or members[0] != span['start'] or members[-1] != span['end'] or event_order[span['start']] > event_order[span['end']]:
+      raise ValueError('tuplet endpoints disagree with member events')
+    if len({ownership[n] for n in members}) != 1 or span.get('voice', ownership[members[0]]) != ownership[members[0]]:
+      raise ValueError('tuplet crosses independent voice lanes')
+    if span.get('bracket', 'auto') not in ('yes', 'no', 'auto') or span.get('show_number', 'actual') not in ('none', 'actual', 'both'):
+      raise ValueError('invalid tuplet appearance')
+    span_ids.add(span['id'])
+  for note in events.values():
+    for verse in note.get('lyrics', []):
+      start = tones[note['pitches'][0]['id']][1] if note['pitches'] else fractions.Fraction()
+      if 'extend_to' in verse and not start < generator.model.fraction(verse['extend_to']) <= absolute:
+        raise ValueError('lyric extension endpoint is outside the score')
+    if any(t not in span_ids for t in note.get('tuplet_ids', [])):
+      raise ValueError('event refers to an unknown tuplet')
+    if tremolo := note.get('tremolo'):
+      if tremolo['type'] not in ('single', 'start', 'stop') or type(tremolo['marks']) is not int or not 0 <= tremolo['marks'] <= 8:
+        raise ValueError('invalid measured tremolo')
+      if tremolo['type'] in ('start', 'stop'):
+        other = events.get(tremolo.get('partner'))
+        expected_type = 'stop' if tremolo['type'] == 'start' else 'start'
+        if not other or other.get('tremolo', {}).get('partner') != note['id'] or other['tremolo']['type'] != expected_type or other['tremolo']['marks'] != tremolo['marks']:
+          raise ValueError('invalid paired tremolo')
+  for span in staves[0].get('octave_shifts', []):
+    if not 0 <= generator.model.fraction(span['start']) < generator.model.fraction(span['end']) <= absolute or not -3 <= span['octaves'] <= 3:
+      raise ValueError('invalid octave-shift span')
+  previous_end = fractions.Fraction()
+  for span in staves[0].get('scale_spans', []):
+    start, end = generator.model.fraction(span['start']), generator.model.fraction(span['end'])
+    if not previous_end <= start < end <= absolute or not isinstance(span.get('label'), str) or not span['label'].strip() or type(span.get('matched')) is not bool:
+      raise ValueError('invalid solo scale span')
+    if not isinstance(span.get('id'), str) or not span['id'] or span['id'] in ids:
+      raise ValueError('solo scale spans require unique IDs')
+    ids.add(span['id'])
+    previous_end = end
diff --git a/generator/vocabulary.py b/generator/vocabulary.py
index d40ba62..263e92a 100644
--- a/generator/vocabulary.py
+++ b/generator/vocabulary.py
@@ -2,12 +2,14 @@
 from __future__ import annotations
 import contextlib
 import contextvars
+import copy
 import dataclasses
+import fractions
 import functools
 import hashlib
 import json
 import pathlib
-import fractions
+import types
 
 ROOT = pathlib.Path(__file__).resolve().parents[1] / 'data' / 'composition'
 ACTIVE = contextvars.ContextVar('composition_vocabulary', default=None)
@@ -16,7 +18,7 @@ def load(root=ROOT):
   # Content, not just the directory, keys memoization. Long-lived individual
   # role builds must observe edited production data without restarting Python.
   names = ('roles', 'harmony', 'lead_ins', 'accompaniment')
-  return _load(tuple((name, (pathlib.Path(root) / (name + '.json')).read_text()) for name in names))
+  return copy.deepcopy(_load(tuple((name, (pathlib.Path(root) / (name + '.json')).read_text()) for name in names)))
 
 @functools.lru_cache(maxsize=16)
 def _load(contents):
@@ -105,26 +107,54 @@ def _load(contents):
 
 @functools.lru_cache(maxsize=1)
 def _default():
-  return {'data': load(), 'role': '', 'settings': {}}
+  return CompositionContext.create(load())
+
+def _freeze(value):
+  if isinstance(value, dict):
+    return types.MappingProxyType({key: _freeze(item) for key, item in value.items()})
+  if isinstance(value, list):
+    return tuple(_freeze(item) for item in value)
+  return value
+
+@functools.lru_cache(maxsize=32)
+def _frozen_json(contents):
+  return _freeze(json.loads(contents))
+
+@dataclasses.dataclass(frozen=True)
+class CompositionContext:
+  """Owned, immutable, pickleable policy inputs with stable iteration order."""
+  resources_json: str
+  name: str = ''
+  settings_json: str = '{}'
+  @classmethod
+  def create(cls, resources, name='', settings=None):
+    return cls(json.dumps(resources), name, json.dumps(settings or {}))
+  def data(self, name):
+    return _frozen_json(self.resources_json)[name]
+  def role(self, name=None):
+    return {**self.data('roles')['roles'].get(name or self.name, {}), **_frozen_json(self.settings_json)}
+  def accompaniment(self, part):
+    value = self.data('accompaniment')
+    return {**{key: item for key, item in value.items() if key != 'instruments'}, **value['instruments'][part]}
 
 def current():
   return ACTIVE.get() or _default()
 
 def data(name):
-  return current()['data'][name]
+  return current().data(name)
 
 def accompaniment(part, resources=None):
-  value = (resources or current()['data'])['accompaniment']
+  if resources is None:
+    return current().accompaniment(part)
+  value = resources['accompaniment']
   return {**{k: v for k, v in value.items() if k != 'instruments'}, **value['instruments'][part]}
 
 def role(name=None):
-  active = current()
-  name = name or active['role']
-  return {**active['data']['roles']['roles'].get(name, {}), **active['settings']}
+  return current().role(name)
 
 @contextlib.contextmanager
 def using(resources, name, settings=None):
-  token = ACTIVE.set({'data': resources, 'role': name, 'settings': settings or {}})
+  token = ACTIVE.set(CompositionContext.create(resources, name, settings))
   try:
     yield
   finally:
diff --git a/include/vamp_zero/score_loader.hpp b/include/vamp_zero/score_loader.hpp
index 423317f..6817b5a 100644
--- a/include/vamp_zero/score_loader.hpp
+++ b/include/vamp_zero/score_loader.hpp
@@ -25,7 +25,8 @@ public:
   // An already-running completion may overlap stop; capture its consumer weakly.
   score_loader(boost::asio::any_io_executor executor,
                std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load,
-               std::function<void()> completed = {});
+               std::function<void()> completed = {},
+               std::optional<boost::asio::any_io_executor> worker = {});
   ~score_loader();
   score_loader(score_loader const &) = delete;
   auto operator=(score_loader const &) -> score_loader & = delete;
diff --git a/include/vamp_zero/ui.hpp b/include/vamp_zero/ui.hpp
index bbfb3e6..3db12cb 100644
--- a/include/vamp_zero/ui.hpp
+++ b/include/vamp_zero/ui.hpp
@@ -4,6 +4,7 @@
 #include <cstdint>
 #include <functional>
 #include <memory>
+#include <optional>
 #include <string>
 
 #include <boost/asio/any_io_executor.hpp>
@@ -24,7 +25,7 @@ class score_loader;
 
 class zero_ui {
 public:
-  zero_ui(boost::asio::any_io_executor executor, luma::application_config config, vamp_zero::database_config database, std::string assets_path, std::function<void(vamp_protocol::page_command)> command_handler = {}, std::function<void(vamp_zero::menu_action)> menu_handler = {});
+  zero_ui(boost::asio::any_io_executor executor, luma::application_config config, vamp_zero::database_config database, std::string assets_path, std::function<void(vamp_protocol::page_command)> command_handler = {}, std::function<void(vamp_zero::menu_action)> menu_handler = {}, std::optional<boost::asio::any_io_executor> score_worker = {});
   ~zero_ui();
   zero_ui(zero_ui const &) = delete;
   auto operator=(zero_ui const &) -> zero_ui & = delete;
diff --git a/src/vamp_zero/app.cpp b/src/vamp_zero/app.cpp
index afac652..b638395 100644
--- a/src/vamp_zero/app.cpp
+++ b/src/vamp_zero/app.cpp
@@ -22,6 +22,7 @@
 #include <boost/asio/post.hpp>
 #include <boost/asio/signal_set.hpp>
 #include <boost/asio/steady_timer.hpp>
+#include <boost/asio/thread_pool.hpp>
 #include <boost/asio/use_future.hpp>
 #include <boost/json/object.hpp>
 #include <boost/json/serialize.hpp>
@@ -322,6 +323,7 @@ private:
 
 auto run_headless(vamp_zero::config const &config, vamp_zero::control_state &state, vamp_zero::audio_controller *audio) -> std::expected<void, modulus::error> {
   auto io = boost::asio::io_context{};
+  auto score_worker = boost::asio::thread_pool{1};
   auto endpoint = make_server_endpoint(config);
   if (!endpoint) {
     return std::unexpected(endpoint.error());
@@ -335,7 +337,7 @@ auto run_headless(vamp_zero::config const &config, vamp_zero::control_state &sta
   if (audio != nullptr) {
     audio->sync(state.snapshot());
   }
-  auto loader = std::make_shared<vamp_zero::score_loader>(io.get_executor(), [executor = io.get_executor(), database = config.database, assets = config.runtime.assets_path](vamp_zero::score_reference reference) { return vamp_zero::async_load_score(executor, database, std::move(reference), assets); });
+  auto loader = std::make_shared<vamp_zero::score_loader>(io.get_executor(), [executor = score_worker.get_executor(), database = config.database, assets = config.runtime.assets_path](vamp_zero::score_reference reference) { return vamp_zero::async_load_score(executor, database, std::move(reference), assets); }, std::function<void()>{}, score_worker.get_executor());
   auto playback = playback_poll{io, state, audio, loader, config.runtime.assets_path, true};
   auto heartbeat = write_heartbeat(config);
   if (!heartbeat) {
@@ -354,11 +356,12 @@ auto run_headless(vamp_zero::config const &config, vamp_zero::control_state &sta
 
 auto run_display(vamp_zero::config const &config, vamp_zero::control_state &state, vamp_zero::audio_controller *audio) -> std::expected<void, modulus::error> {
   auto io = boost::asio::io_context{};
+  auto score_worker = boost::asio::thread_pool{1};
   auto endpoint = make_server_endpoint(config);
   if (!endpoint) {
     return std::unexpected(endpoint.error());
   }
-  auto ui = vamp_zero::zero_ui{io.get_executor(), config.display, config.database, config.runtime.assets_path, [&state](vamp_protocol::page_command command) { static_cast<void>(state.apply(command)); }, [&state](vamp_zero::menu_action action) { static_cast<void>(state.apply(action)); }};
+  auto ui = vamp_zero::zero_ui{io.get_executor(), config.display, config.database, config.runtime.assets_path, [&state](vamp_protocol::page_command command) { static_cast<void>(state.apply(command)); }, [&state](vamp_zero::menu_action action) { static_cast<void>(state.apply(action)); }, score_worker.get_executor()};
   state.set_observer([&ui](vamp_zero::app_state app) {
     auto status = ui.publish(std::move(app));
     if (!status) {
diff --git a/src/vamp_zero/score_loader.cpp b/src/vamp_zero/score_loader.cpp
index 0f54dce..455f84d 100644
--- a/src/vamp_zero/score_loader.cpp
+++ b/src/vamp_zero/score_loader.cpp
@@ -6,6 +6,7 @@
 #include <utility>
 
 #include <boost/asio/co_spawn.hpp>
+#include <boost/asio/bind_executor.hpp>
 #include <boost/asio/post.hpp>
 
 #include <vamp_zero/errors.hpp>
@@ -13,8 +14,8 @@
 
 
 struct vamp_zero::score_loader::state : std::enable_shared_from_this<state> {
-  state(boost::asio::any_io_executor executor, std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load, std::function<void()> completed)
-      : executor{std::move(executor)}, load{std::move(load)}, completed{std::move(completed)} {}
+  state(boost::asio::any_io_executor executor, std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load, std::function<void()> completed, std::optional<boost::asio::any_io_executor> worker)
+      : executor{executor}, worker{worker.value_or(executor)}, load{std::move(load)}, completed{std::move(completed)} {}
   static auto run(std::weak_ptr<state> weak, std::uint64_t generation, std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load, vamp_zero::score_reference reference) -> boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>> {
     {
       auto self = weak.lock();
@@ -63,15 +64,16 @@ struct vamp_zero::score_loader::state : std::enable_shared_from_this<state> {
   auto start() -> void {
     in_flight = true;
     // post is required: co_spawn can enter inline on an already-running executor.
-    boost::asio::post(executor, [weak = weak_from_this(), generation = generation, load = load,
-                                 reference = *reference, executor = executor]() mutable {
-      boost::asio::co_spawn(executor, run(weak, generation, std::move(load), std::move(reference)),
-                            [weak, generation](std::exception_ptr exception, std::expected<vamp_zero::score_document, modulus::error> loaded) {
+    boost::asio::post(worker, [weak = weak_from_this(), generation = generation, load = load,
+                               reference = *reference, executor = executor, worker = worker]() mutable {
+      boost::asio::co_spawn(worker, run(weak, generation, std::move(load), std::move(reference)),
+                            boost::asio::bind_executor(executor, [weak, generation](std::exception_ptr exception, std::expected<vamp_zero::score_document, modulus::error> loaded) {
                               finish(weak, generation, exception, std::move(loaded));
-                            });
+                            }));
     });
   }
   boost::asio::any_io_executor executor;
+  boost::asio::any_io_executor worker;
   std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load;
   std::function<void()> completed;
   std::mutex mutex{};
@@ -83,8 +85,8 @@ struct vamp_zero::score_loader::state : std::enable_shared_from_this<state> {
   std::bool_t stopped{};
 };
 
-vamp_zero::score_loader::score_loader(boost::asio::any_io_executor executor, std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load, std::function<void()> completed)
-    : state_{std::make_shared<state>(std::move(executor), std::move(load), std::move(completed))} {}
+vamp_zero::score_loader::score_loader(boost::asio::any_io_executor executor, std::function<boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>>(vamp_zero::score_reference)> load, std::function<void()> completed, std::optional<boost::asio::any_io_executor> worker)
+    : state_{std::make_shared<state>(std::move(executor), std::move(load), std::move(completed), std::move(worker))} {}
 
 vamp_zero::score_loader::~score_loader() {
   stop();
diff --git a/src/vamp_zero/ui.cpp b/src/vamp_zero/ui.cpp
index 851dcc3..66a8049 100644
--- a/src/vamp_zero/ui.cpp
+++ b/src/vamp_zero/ui.cpp
@@ -184,13 +184,13 @@ private:
 
 }
 
-vamp_zero::zero_ui::zero_ui(boost::asio::any_io_executor executor, luma::application_config config, vamp_zero::database_config database, std::string assets_path, std::function<void(vamp_protocol::page_command)> command_handler, std::function<void(vamp_zero::menu_action)> menu_handler)
+vamp_zero::zero_ui::zero_ui(boost::asio::any_io_executor executor, luma::application_config config, vamp_zero::database_config database, std::string assets_path, std::function<void(vamp_protocol::page_command)> command_handler, std::function<void(vamp_zero::menu_action)> menu_handler, std::optional<boost::asio::any_io_executor> score_worker)
     : application_{std::make_shared<luma::application>(std::move(config))},
       runtime_{std::make_shared<vamp_zero::ui_runtime>(executor, std::move(command_handler), std::move(menu_handler))},
-      score_loader_{std::make_shared<vamp_zero::score_loader>(executor, [executor, database = std::move(database), assets = std::move(assets_path)](vamp_zero::score_reference reference) { return vamp_zero::async_load_score(executor, database, std::move(reference), assets); }, [weak = std::weak_ptr{application_}] {
+      score_loader_{std::make_shared<vamp_zero::score_loader>(executor, [executor = score_worker.value_or(executor), database = std::move(database), assets = std::move(assets_path)](vamp_zero::score_reference reference) { return vamp_zero::async_load_score(executor, database, std::move(reference), assets); }, [weak = std::weak_ptr{application_}] {
           if (auto application = weak.lock()) {
             static_cast<void>(application->request_layout());
-          } })} {}
+          } }, score_worker)} {}
 
 vamp_zero::zero_ui::~zero_ui() {
   stop();
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 074d7f2..6eb3693 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -61,6 +61,11 @@ add_test(
 # Complete deterministic phrase searches make this suite CPU-sensitive;
 # leave headroom for concurrent asset generation on development machines.
 set_tests_properties(product_vamp_generator PROPERTIES TIMEOUT 600)
+add_test(
+  NAME product_vamp_assets
+  COMMAND ${VAMP_PYTHON_COMMAND} -m tests.asset_contract ${CMAKE_BINARY_DIR}/generated_assets
+  WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}
+)
 add_custom_target(check
   COMMAND ${CMAKE_CTEST_COMMAND}
     --test-dir ${CMAKE_BINARY_DIR}
diff --git a/tests/asset_contract.py b/tests/asset_contract.py
new file mode 100644
index 0000000..08ac38d
--- /dev/null
+++ b/tests/asset_contract.py
@@ -0,0 +1,17 @@
+"""Compare complete generated assets with the reviewed, pinned output baseline."""
+import hashlib
+import json
+import pathlib
+import sys
+
+def verify(root):
+  expected = json.loads(pathlib.Path(__file__).with_name('fixtures').joinpath('assets_manifest.json').read_text())
+  actual = {path.relative_to(root).as_posix(): hashlib.sha256(path.read_bytes()).hexdigest()
+    for path in sorted(root.rglob('*')) if path.is_file() and path.relative_to(root).parts[0] != 'analysis'}
+  changed = sorted(name for name in expected.keys() | actual.keys() if expected.get(name) != actual.get(name))
+  if changed:
+    raise AssertionError('Generated assets differ from the reviewed baseline:\n' + '\n'.join(changed))
+  print(f'All {len(expected)} generated assets match the reviewed baseline.')
+
+if __name__ == '__main__':
+  verify(pathlib.Path(sys.argv[1]))
diff --git a/tests/fixtures/assets_manifest.json b/tests/fixtures/assets_manifest.json
new file mode 100644
index 0000000..e80b7a0
--- /dev/null
+++ b/tests/fixtures/assets_manifest.json
@@ -0,0 +1,411 @@
+{
+  "backing/all_of_me_120.wav": "5104097be1d4ed0459dacedb61c2509effcfe0e26025b24574291a3467962f3d",
+  "backing/autumn_leaves_120.wav": "990e0218f9a09161a7a8a255bd1e64daf9fd01ac41935faa273228906775d016",
+  "catalog.db": "0891794877e06d201e1e149ea82f7bfdc880baf35c78a29b7b724f6c0ecce1e9",
+  "fonts/petaluma/OFL.txt": "5789e74d38031e93a4fbdb0a72392d1fd58cf15c29da3efa695c5099433ad0ce",
+  "fonts/petaluma/PetalumaScript.otf": "3b4be972cc9f857a7c1019ff49cd07cb083d5cc99058c0fb8563897fc75c32c8",
+  "pico/titles/42076b2eaa61a6fb408eeaec133b130967cf2c32981a9444dde6903ed7771fc8.mask": "42076b2eaa61a6fb408eeaec133b130967cf2c32981a9444dde6903ed7771fc8",
+  "pico/titles/8ed7df6668e9e4a24c148ba0fe9ac57209e504ca6a7e8a9b29179c097076ecae.mask": "8ed7df6668e9e4a24c148ba0fe9ac57209e504ca6a7e8a9b29179c097076ecae",
+  "print/all_of_me_acoustic.pdf": "aff0697fa82bde5283f705395028a3e4f6e87d4e0f1eab271dea9cffdb6c72e2",
+  "print/all_of_me_electric.pdf": "1185ece1e8f507d6fd7046e9d78fcb28b9e0a667c1027304abcb13c8e0519b97",
+  "print/all_of_me_vocal.pdf": "0ff78cb9d315dff93e7a88209610e959fa804c480cf63a8c4fb018a17c46ff66",
+  "print/autumn_leaves_acoustic.pdf": "badafe4d5484ab7e8a7c94633174d2233233436318fcf62bfcc043f624d097d6",
+  "print/autumn_leaves_electric.pdf": "a7416f9c4390072f74736024162172340d273de5108681bdf6543c9b8fa69d60",
+  "print/autumn_leaves_vocal.pdf": "78cc66dd27c7088e196f917eb752266989de13c51361692195b6bb9765210001",
+  "songs/all_of_me_acoustic.json": "b5f9f3781a79a351a59bbb54a333cbb1dac9e21c46a33c4296d6baef0ed8ff41",
+  "songs/all_of_me_acoustic.pages/0001.png": "165e827c3a05c1ee2aa1e5fd41c9dd2b273dac04e067df6d3e136f16fd2255a1",
+  "songs/all_of_me_acoustic.pages/0002.png": "b8738a70ad3d32911a8147ff18e62e4aa26651277562c348cb28f9180f045888",
+  "songs/all_of_me_acoustic.pages/0003.png": "af9631bdb1736de168527ac7a881de5c7b9fa1fe532aa10bffe4b4419cb67297",
+  "songs/all_of_me_acoustic.pages/0004.png": "8b2fdc7a064945bdfafb77b9a5f87313a86ef759a87daedb861cd3822dd2fdd2",
+  "songs/all_of_me_acoustic.pages/0005.png": "c11b85ac3affe9cee9184c126dd9cbffea5ef01d5f238440f831ce80b477f09b",
+  "songs/all_of_me_acoustic.pages/0006.png": "28bcdd62274aa79a6626935279dd88a9c85223f9ee3e4e7e914cd2ff56c704b6",
+  "songs/all_of_me_acoustic.pages/0007.png": "bfe462e693c5eb849b53463b2d64ba201e11196f64d5ec94e7d80a00f437d95f",
+  "songs/all_of_me_acoustic.pages/0008.png": "a7fa969178c12295a31429289b6d7ec273cc6e388343c174793d503856084c2c",
+  "songs/all_of_me_acoustic.pages/0009.png": "19a2fb51af8e4e09dafcba21b4e2277052125bb34222d2b1638a75582266bcea",
+  "songs/all_of_me_acoustic.pages/0010.png": "d423c4a0ae3c9d5e626bf8a633b202501ea5768c83ddbf68a6df8265d2a88315",
+  "songs/all_of_me_acoustic.pages/0011.png": "5e21353bfac521f66b49b6cd4e0dc00c4e85c27bac41d69809b8f88f3e9be310",
+  "songs/all_of_me_acoustic.pages/0012.png": "c36c7a82d1900f5394b1af3ab0bf663055e2bd7a1788fd60f416d7ec17902c7a",
+  "songs/all_of_me_acoustic.pages/0013.png": "063ba3b58613d9c383e379b0c6fa9b2d8b620cff5ff4def145fca918fa80f5e0",
+  "songs/all_of_me_acoustic.pages/0014.png": "ae3622cc934dbc126bff80f02bda6159edabd5044b5fc6c2448161652dc983ad",
+  "songs/all_of_me_acoustic.pages/0015.png": "99acae22eadaacd195fd986ae31f10c32800972e4d164f82cb5151ee5691c030",
+  "songs/all_of_me_acoustic.pages/0016.png": "c73a7111028d2e875ed441c54f9299b93947f53738e1815cb463d8a84fb7ef19",
+  "songs/all_of_me_acoustic.pages/0017.png": "6fa69caf6a91a38b3da2c57c146f4e79be712237b54910afe22d504cb7b46004",
+  "songs/all_of_me_acoustic.pages/0018.png": "f92e147f22c688b8936a7f2589b8ad6b7337e7b0aa9d9136641cff269623945b",
+  "songs/all_of_me_acoustic.pages/0019.png": "de5094eb5c2809146af4dc5470d58ab8ae70feb138d6fca83aa837aeb5bacc36",
+  "songs/all_of_me_acoustic.pages/0020.png": "d7c14a96a210c03918ad1c42240b34b27baf3412d03a443a0e51ffc631b27569",
+  "songs/all_of_me_acoustic.pages/0021.png": "81435e1c822309d48cd80a454a468e595f98684b8fc13e9aab61e7f9efbc8326",
+  "songs/all_of_me_acoustic.pages/0022.png": "78e7d1cc5b05ea1dd59b396d3554ee6b335b30d4adfc92d9da7deb80e420865c",
+  "songs/all_of_me_acoustic.pages/0023.png": "ed8a533012b886e46430d25b21d2a7e6ff026399f1f04a6561d8b8c465e7edf8",
+  "songs/all_of_me_acoustic.pages/0024.png": "d1ef3d847cc874f50fe1f7e84acba316431a56ef04101371c5eeefb38e03f54d",
+  "songs/all_of_me_acoustic.pages/0025.png": "6c22754c4af52c0bc1b986a9bb40d2611eaf19b891686d4fdd7082a7b37ae700",
+  "songs/all_of_me_acoustic.pages/0026.png": "f7433c965a235e41952d8d259c9aea0630792fe0470360208eba22d50ca2bc12",
+  "songs/all_of_me_acoustic.pages/0027.png": "2a7f5cb133d68b538f4ffb6e99a531a0416dcc62b8b35b9fdd002ada3277474a",
+  "songs/all_of_me_acoustic.pages/0028.png": "7c5a369f5dc4acef1bcc270543d6d8075a7066ceafa1cf2fabeca0fb78bcd9f7",
+  "songs/all_of_me_acoustic.pages/0029.png": "b58871c97069f13a3d5af60473af5aa5fb081e3373424b7761ca6f312f06e45b",
+  "songs/all_of_me_acoustic.pages/playback-0002.png": "89275aa531c7787a33b1450a8e84afbdb7d952a42f0b2105b58fca57243ed8d6",
+  "songs/all_of_me_acoustic.pages/playback-0003.png": "838b2d12000f748c0fd102de50eaea0ca3950cef07c051c6657d81f628169297",
+  "songs/all_of_me_acoustic.pages/playback-0004.png": "439e1856d32875c83d8d156bc9aa9f11bc493564bb342cf99044bf578980e25e",
+  "songs/all_of_me_acoustic.pages/playback-0005.png": "7789a952684a77309e19ca867a5500928fc96f67f5f82f371b346c9153778e96",
+  "songs/all_of_me_acoustic.pages/playback-0006.png": "ced45cec6c95fb0616552be40cf0543f9ab730ba0cf2414e72b156c12a74a9bc",
+  "songs/all_of_me_acoustic.pages/playback-0007.png": "2ed7cca6a962fead8ffcc95361aa3549e664038d99be1ec3d258ed51e917a53d",
+  "songs/all_of_me_acoustic.pages/playback-0008.png": "3efcd0671de4d386b189181ee7ebe03d4c50eddcfa9080c07a99c4642d4d58aa",
+  "songs/all_of_me_acoustic.pages/playback-0009.png": "cc4dc2ccfccda12074d69452e8e0427d40e6a0c9fb3b3da8308ab3b84240dbb2",
+  "songs/all_of_me_acoustic.pages/playback-0010.png": "fca310b66181635a06f6da5150a7e6ea13ce169aae94fe722139c371f5bbe1b6",
+  "songs/all_of_me_acoustic.pages/playback-0011.png": "dc92c989d193387eb5cc690b8274e57326eea652fa18688e37d405ca69cef051",
+  "songs/all_of_me_acoustic.pages/playback-0012.png": "7043e31820e325d716e7fa77992d4e416a7c9b8cf6391fc87e71ae6c685a75f8",
+  "songs/all_of_me_acoustic.pages/playback-0013.png": "67fbc90a1d4c3b2455bae0d0fb8f035430ad8cfed8f45a3a87988116cad5aeea",
+  "songs/all_of_me_acoustic.pages/playback-0014.png": "93561857be092664c798e2dd04cc6c15284c2a2e1759a056a978242f3b86e3ab",
+  "songs/all_of_me_acoustic.pages/playback-0015.png": "1ae5794742afae872c34f3bf1d21f3f6276d8ede4cca737ee5b58bc0a6c4b627",
+  "songs/all_of_me_acoustic.pages/playback-0016.png": "99274eea14c17d69f7fa940cc2dd14148e1406f4b3ed37fbabe72e1edcbc09b9",
+  "songs/all_of_me_acoustic.pages/playback-0017.png": "ac38a8f3c94e7a331516c90a46daa435f5c820a7db9527895dfccb2c4f2d4b3d",
+  "songs/all_of_me_acoustic.pages/playback-0018.png": "02c1308be295df3a8e1464e8809acbf9fb283d5e0bc400d30c99cba6f383f4d4",
+  "songs/all_of_me_acoustic.pages/playback-0019.png": "b009489f22aea8f68c8ad4ae0e09f7244c75e330245032ffe31bcf4812bf14b3",
+  "songs/all_of_me_acoustic.pages/playback-0020.png": "5a57c46ec799b8588ac42d7cf5bc98d5597302bde4d75745be343428cd4cbf74",
+  "songs/all_of_me_acoustic.pages/playback-0021.png": "184d0d6fbf9864dd2e3ab2a947eb21fa0ba6ef8ffc19f4ff4e05902b640c48d9",
+  "songs/all_of_me_acoustic.pages/playback-0022.png": "d4edcc5eb21d4b1fd97110a4e063cd1997f9f490012ea15f54f2a54ff71f0533",
+  "songs/all_of_me_acoustic.pages/playback-0023.png": "4fc5208032155c47172d7868529876b798596f73c9cca31bf68f4d7a63fa5660",
+  "songs/all_of_me_acoustic.pages/playback-0024.png": "5451f8652c7b7966d20db24fc07229dbc8839b63b04f318a7682c63e04216287",
+  "songs/all_of_me_acoustic.pages/playback-0025.png": "2b607bd202d85aef6d9b87d51a0cf16c6d15a14ab00ed4e894be7bdd9e5cfb77",
+  "songs/all_of_me_acoustic.pages/playback-0026.png": "a741f9177b792d6392eeaa1dc098df7f503e3a829fc862dabf0fc89a2334d6f1",
+  "songs/all_of_me_acoustic.pages/playback-0027.png": "2bf42f6fc15e0941c54f9f098f4983f2f45d9a7567eaa604a6b6319c0ce31c19",
+  "songs/all_of_me_acoustic.pages/playback-0028.png": "bead93f269e3ea6a91a0e71a03eb3e386c8a0f972034e7e3e23cf8807de2e589",
+  "songs/all_of_me_acoustic.pages/playback-0029.png": "196dd7c0f49190342cbcf4e88267462ea4fd353949f1a66fba0d129349579f85",
+  "songs/all_of_me_acoustic.pages/playback-0030.png": "339afb9ccf4e5fc0b18205aa3154ec0494d873494245f14512d1c77e7acdb3f2",
+  "songs/all_of_me_acoustic.pages/playback-0031.png": "f30c7d9824cf9eee91050879ee1b406e608d47461fa5de720639ce060ac10368",
+  "songs/all_of_me_acoustic.pages/playback-0032.png": "421170df4fdb0b746077ba2959ff33480c05edfaffc2505e7ebcf51a9aecf2ca",
+  "songs/all_of_me_acoustic.pages/playback-0033.png": "2af68de5667ca9b8d738703c562c0338e8c2fb5face892d07eb2894cb7b8e6c8",
+  "songs/all_of_me_acoustic.pages/playback-0034.png": "da78e34c05b7527c636124a349a38a95201173ca59d5778a88b7ad19fd458973",
+  "songs/all_of_me_acoustic.pages/playback-0035.png": "d3b699e968ef04d32f3330a4af99e4722f0bf436daaa818e16ea8076dd35968f",
+  "songs/all_of_me_acoustic.pages/playback-0036.png": "48c5688c1368946da513361c0e241ad13157fe7cf4dcaec216fe85031e63455f",
+  "songs/all_of_me_acoustic.pages/playback-0037.png": "e11a4272fe7596b73ac1ed2029c259268c0255bdf4805026fd28412c955a9b88",
+  "songs/all_of_me_acoustic.pages/playback-0038.png": "2ed4ea3113dfdf04f5416154904fc2bd409024e6beca62823bf8d49306f9dd32",
+  "songs/all_of_me_acoustic.pages/playback-0039.png": "506e04f4080141b20b51122756e1fb636b795b0c7a9cfea794787ef8f6d20b28",
+  "songs/all_of_me_acoustic.pages/playback-0040.png": "71b20e99fd27f4222435cb1349df375fc93f0749e6c07bc49946493044cfb088",
+  "songs/all_of_me_acoustic.pages/playback-0041.png": "01e099e1e9bb31eb89c0806ca3885793373243de5cb759b87782aba64548eca0",
+  "songs/all_of_me_acoustic.pages/playback-0042.png": "a26dc16d90c54856c8897fac364be9d4a5e67616afcd863582e4f36c14e689c2",
+  "songs/all_of_me_acoustic.pages/playback-0043.png": "1385cc3c40f04f897b69f277dc0f89a3c70fb0f4509722f13ab3f8a08d4a301b",
+  "songs/all_of_me_acoustic.pages/playback-0044.png": "c12d277f421d3120d318bf7ad14662153a1fa7af6941dd0362da460e967e0312",
+  "songs/all_of_me_acoustic.pages/playback-0045.png": "95c52e795b0aff090ce88d8f3048ccb1bfedb478a8ea0fc9611843e7d3233b33",
+  "songs/all_of_me_acoustic.pages/playback-0046.png": "f4fb50ff913ba429633c2e80c5dac60fa16dd3ea9a1c4873794f1e482c6c9c90",
+  "songs/all_of_me_acoustic.pages/playback-0047.png": "9ce7a7f624a654561fd132628400a16e95665cbc8bc33c437c7d21835de18adf",
+  "songs/all_of_me_acoustic.pages/playback-0048.png": "2faf0c360563387702a2244b26dba8885d5227c3ded4238d480fb81b607531f5",
+  "songs/all_of_me_acoustic.pages/playback-0049.png": "4e94b56e4962ad097bf6ad703be517215b11749e234efc86b7bf1e7ed845f0a2",
+  "songs/all_of_me_acoustic.pages/playback-0050.png": "aeeea727737f35d556abba012444551fde6f1202f99e0959b807d39840384801",
+  "songs/all_of_me_acoustic.pages/playback-0051.png": "7f918b1847cf774167f62437cc5524b2d7465355e7d3a34bc1778e0c5e01df7f",
+  "songs/all_of_me_acoustic.pages/playback-0052.png": "5da7caa11f7d223c7be0baf95d049ee226a28236c91a7fe3c95424fe509c5f63",
+  "songs/all_of_me_acoustic.pages/playback-0053.png": "6dae421ab2d5a85d253f0cc6a750d562a47f2a4c782fc70259c0d0dcdd5f6008",
+  "songs/all_of_me_acoustic.pages/playback-0054.png": "9a3cd474eaadf4c40b3df43ec805d47d1bc81110d0c56d1e17356d550b731cef",
+  "songs/all_of_me_acoustic.pages/playback-0055.png": "6489f62576b32c1c7071361fa9d3db372a47927d66f6865ee417bb99c9c04c15",
+  "songs/all_of_me_acoustic.pages/playback-0056.png": "f7ab14f136adcc844acec06935fdfec2b166972f6c7d6b3993883aaa0ca9e859",
+  "songs/all_of_me_acoustic.pages/playback-0057.png": "8fcc3723e92877b1005cedba8045a4488e5134e3f1f2185a465b8b6115823f4f",
+  "songs/all_of_me_acoustic.pages/playback-0058.png": "7d0a9ef281a2e38814506d04932276bcb5041c1c3947dd6aaa874ff066a038fd",
+  "songs/all_of_me_electric.json": "ae2bf27df59d93436bdcb8ae67821e635014e104e64ec8a4585326bc4bdc087a",
+  "songs/all_of_me_electric.pages/0001.png": "4080b675aeb49f1b745a18641fc284235b9c3f5e36d07bf258772300f6fed6b8",
+  "songs/all_of_me_electric.pages/0002.png": "b4d590883d16efdd43d8199324bb825ac23d84f1f5d4fc5c5131a82d504eb756",
+  "songs/all_of_me_electric.pages/0003.png": "6d16d6d083ddc2c3025c1b379cc145cb0e1de8074e7a51bfcaa817089c51e7a7",
+  "songs/all_of_me_electric.pages/0004.png": "106a0cd8cd598455a9694d62c3bc905c6e8f038910b40efabafdf43cf2836642",
+  "songs/all_of_me_electric.pages/0005.png": "5e69575380ed38032dc7ede57d4e815540e15eaa8fad7baeee3d60dd84b7d70b",
+  "songs/all_of_me_electric.pages/0006.png": "d21342d7e8dd3a63c246ae37dd69567914cb7c3e6c5171de04ed0ffbdc008717",
+  "songs/all_of_me_electric.pages/0007.png": "c418f413c20c48ce85fcb86ab20eb64d1b9635a45adaac8acfc54403ab2477b9",
+  "songs/all_of_me_electric.pages/0008.png": "166c390f64d654ac0adba802c45b2c5f3c47bcacf57a4180ddb0f36597f349f9",
+  "songs/all_of_me_electric.pages/0009.png": "c50e6e4582423176dd2c4e52933eb6263192350f63d16192bd13842d1bd901c8",
+  "songs/all_of_me_electric.pages/0010.png": "50b939ff62a4430102cd0d851758a326a7d9ee4478afc6471428c3b20692a154",
+  "songs/all_of_me_electric.pages/0011.png": "2a063242e638507b6978f03043505c441b392ab90943e8b8f39c9a5b6489105c",
+  "songs/all_of_me_electric.pages/0012.png": "843fd8cd70334df8b327e1316fd3df00efba5f2e7587abc96f14808f25d785ba",
+  "songs/all_of_me_electric.pages/0013.png": "d1648e1633ad74b790d1b21d3ac85946ea66e048ac8ebebc338dc58eba1453aa",
+  "songs/all_of_me_electric.pages/0014.png": "5859ff6cd737294f010ecfcf9202924530c037b56e14ffbb29ea7f3fc712a11f",
+  "songs/all_of_me_electric.pages/0015.png": "b38390c67e0e56a9218f1fd82d386583f8a5fb827255357d6d375ece7cc4e39a",
+  "songs/all_of_me_electric.pages/0016.png": "ce83a70d0c06b0fee259c1b537b889aa82e74f058a3d46edcbe2956a7cb96aa0",
+  "songs/all_of_me_electric.pages/0017.png": "97b5da09798a71b8ceae26748da222ea6a90dab14dd59ae4e0eddf55f42d706f",
+  "songs/all_of_me_electric.pages/0018.png": "124accb8cbb0b8becc086a3e0883052d1d44add715adc46c7fe1e4d1c65d0c62",
+  "songs/all_of_me_electric.pages/0019.png": "f3886454bbce1128ec0de1de71a2a1dba4dcec41b68fedf815a2c22280c83708",
+  "songs/all_of_me_electric.pages/0020.png": "6c78af0299bc6cc344800a18f3eeb310ef273f732588dd6d131a9315660c6c8b",
+  "songs/all_of_me_electric.pages/0021.png": "8d248495a0a6c711d1619475ffafb16ad6f831a6246bb0c32cb2500e69d0ad8b",
+  "songs/all_of_me_electric.pages/0022.png": "42e5cf25476df3a4ee8030a32d3522401f5de45c539504e544780ebb862bc3c2",
+  "songs/all_of_me_electric.pages/0023.png": "a7dfa4060c0b5fc26440ed299466db702eeb2cf80cd40c91f83e031f8be53b93",
+  "songs/all_of_me_electric.pages/playback-0002.png": "403f0cfd04a73ecc7d6277c1ad5d6f0638218386d71a18a960316ad75625de3a",
+  "songs/all_of_me_electric.pages/playback-0003.png": "0aaa246f780dcdce077fadf99f0bb2febb47eb70462c341545a01c351fa03a18",
+  "songs/all_of_me_electric.pages/playback-0004.png": "f272b7991e1e2721dea59fdc74836421ef501f7b937b5487ce82985d54feb65e",
+  "songs/all_of_me_electric.pages/playback-0005.png": "227c94ab1b8f2d28cda0cf2c55710796b1739f48e4e47ae8d88af5b3e7f3fa71",
+  "songs/all_of_me_electric.pages/playback-0006.png": "196910b9157c0fd142aed1555e294068a726ebf4a12fb077953ab4ffa078cc3b",
+  "songs/all_of_me_electric.pages/playback-0007.png": "65a2e7466bed99e53a52fa6135926a5d11309e2f5141b14dc1ecde85bb4a2974",
+  "songs/all_of_me_electric.pages/playback-0008.png": "d28dd164add8c1081408f6310bddad34f60c8fbbf2559d88f8d3024ff089ae18",
+  "songs/all_of_me_electric.pages/playback-0009.png": "7f9814e8de25ffa797cfcb723bf0146943d9dd0b3c7708e1b8eee34ccdcf65c9",
+  "songs/all_of_me_electric.pages/playback-0010.png": "0aeb5e7a51504708f1ac1a7f971c8bfd6164745ac334a44cdceb3ddc3cdc62d2",
+  "songs/all_of_me_electric.pages/playback-0011.png": "d3f67966eb3cc8a5198f8c5832ed9387607e3c657ba730361c06bee9bdeb8862",
+  "songs/all_of_me_electric.pages/playback-0012.png": "21e1f3c7978796f5b82aa3cf126ece81e409f6c48129681292f5703fb05dc371",
+  "songs/all_of_me_electric.pages/playback-0013.png": "6cbfc21a3ecdf4980b10636b8374cb918ff017abc5592dc9aef4edf55d27ddbd",
+  "songs/all_of_me_electric.pages/playback-0014.png": "dd2d3cf5ed13638c91a4b9f92462200494bc78001062f38d8be172d08804e5cf",
+  "songs/all_of_me_electric.pages/playback-0015.png": "e9dd230dd3410f8ccc6ba55c04155653a02a7cc54ba9903f07bd115894d57019",
+  "songs/all_of_me_electric.pages/playback-0016.png": "870884db997e94c9bafa6f8a173059dffa55f99f3a38e400e59658a251737b97",
+  "songs/all_of_me_electric.pages/playback-0017.png": "21f0489f8f948e4131a7c14585169f0d4e9795166a75459eeadc698a49e7c36a",
+  "songs/all_of_me_electric.pages/playback-0018.png": "e834520df8a74a2f762044d4d2a0bc220124227e348555b33bf73dca11d848a2",
+  "songs/all_of_me_electric.pages/playback-0019.png": "d046a861e398d0fa4e2eb0bd316f6101455e4c27cb9c73ece1c7a7e8e296032f",
+  "songs/all_of_me_electric.pages/playback-0020.png": "979701ac47e9cdcd4f21fd63af0dac2e0fede6567c9bb417c4a3133b99df66ee",
+  "songs/all_of_me_electric.pages/playback-0021.png": "62edac1a5171cd41a1e9eeaf67991ec7574941bb03a74e2bd742ea68840617f8",
+  "songs/all_of_me_electric.pages/playback-0022.png": "343e6c59f3f3b5718df93d3ef871ca6e041a0a674d719df122b6ab298dcd96ba",
+  "songs/all_of_me_electric.pages/playback-0023.png": "14735b44d4a7b65b957c1d733e7082c639a0e4acc9caffffde1b7bddf236eee7",
+  "songs/all_of_me_electric.pages/playback-0024.png": "cc21f078595a1fd138f00153b30cebcccecd0acc8c8b4a4a17e7908ad854e1a6",
+  "songs/all_of_me_electric.pages/playback-0025.png": "ce3df5c546abada13bf1cc0b409d30239df2bc9eff0f7d04857c75b4734bc642",
+  "songs/all_of_me_electric.pages/playback-0026.png": "367021a47fac7e2dc54e3288399b708ae46bd21a6055e8593eead39d1b195d58",
+  "songs/all_of_me_electric.pages/playback-0027.png": "8544e3d66736b42b4b4c6f4433b00945f14aabdf2fa02159e666e5005f66206e",
+  "songs/all_of_me_electric.pages/playback-0028.png": "96d88ee25fe1e2543fb0599a5e6f18f6fa20430146a3cbe2ec1cb4e164776943",
+  "songs/all_of_me_electric.pages/playback-0029.png": "689aac0d1696ce3940d05bceadad057c485bd36ffe6615aa679ee974c36b2cf1",
+  "songs/all_of_me_electric.pages/playback-0030.png": "c9961fb33a22d8cfe0ac23b708b491c8fe066c28565f946634aa35ecc50d2164",
+  "songs/all_of_me_electric.pages/playback-0031.png": "eb03bc4ff5d5037c5e068323060610f268678a4c8083d3f4f727c7171cc6b1cb",
+  "songs/all_of_me_electric.pages/playback-0032.png": "6ee11cbeb454dd51199b702178f54c8c17bb626542776419818477c77bb5c6e6",
+  "songs/all_of_me_electric.pages/playback-0033.png": "8b0bc5cd261d542f6aad5ba56d23aabba32892739b32e09e84f0c147beea7708",
+  "songs/all_of_me_electric.pages/playback-0034.png": "f413fb00b1231b1783a0578063212217043adc73a270c23cad8c8913bfd70e98",
+  "songs/all_of_me_electric.pages/playback-0035.png": "88f772174ce53af5d84ac4d804d827e4c3096ff64126b0ea2eb206589d75fe46",
+  "songs/all_of_me_electric.pages/playback-0036.png": "f0e09108d57afdc64791164cb8df197ff1794e5df3bd803325b1ab4ec904d761",
+  "songs/all_of_me_electric.pages/playback-0037.png": "b1a6b868a18f4a5b18dfb8b11d38ed5e5505c3a1736cf4d71172c6f75d9e6c22",
+  "songs/all_of_me_electric.pages/playback-0038.png": "aaef3ac9fc6d52703bb4bbfe588c51f630e6cef75a85fa9cbd3197c5c252bb23",
+  "songs/all_of_me_electric.pages/playback-0039.png": "43606ff740a8127560d60a384b9ca910a294cb96de13f3da2492a646097abe82",
+  "songs/all_of_me_electric.pages/playback-0040.png": "8f7809d7a0fcad64e9a7c5ab644b7de771460d7d48b554ef603d0c93a98a0124",
+  "songs/all_of_me_electric.pages/playback-0041.png": "7c0befdd861d8a98d170c04fa813a0c091568bf74bf94fcc14024ce7618d016f",
+  "songs/all_of_me_electric.pages/playback-0042.png": "349e59923c00ccd2675f61763dcb2bc81d9debe3efac409e0b25d8bcd1e3bd42",
+  "songs/all_of_me_electric.pages/playback-0043.png": "90c5d4f9149e380fcfcfdb18882381f535c8f619b475c480210dffe3570a3d8f",
+  "songs/all_of_me_electric.pages/playback-0044.png": "3548e497fe84e7a6f3344cdd5bfb7b4d44e89b6f2cc6778a8bf891fdb0d95ae3",
+  "songs/all_of_me_electric.pages/playback-0045.png": "1f21274695106a635e92551f7d12b739a82f1a5a17db8d911e60a00fca170e10",
+  "songs/all_of_me_vocal.json": "04c2712621766ee10529135463c0ceeffdd2def707134c81fb450e30a2d6cd67",
+  "songs/all_of_me_vocal.pages/0001.png": "5ff59ef10db0937c0dc132effc4f1ab761c6a4cdd9898aed1cbfc79c3ee126ad",
+  "songs/all_of_me_vocal.pages/0002.png": "8c737499c4e537b779160b86bf779de9b0a6771ece8f594af64ccd66e896f0d6",
+  "songs/all_of_me_vocal.pages/0003.png": "1ae152662e101117056704e7ccc92e7fadf546e4b0b68b11a463b8a778a2449e",
+  "songs/all_of_me_vocal.pages/0004.png": "d921899d08554455d72c71709d1110d808c5227de5cfc0c9aff68a168c7d4ecb",
+  "songs/all_of_me_vocal.pages/0005.png": "4c9fb6f70a887dceb7aca582122c7ba3d06a38431a37247b422e11a81f917e5e",
+  "songs/all_of_me_vocal.pages/0006.png": "a2792f1dc70d11d7f1b26f4c51686c8c6739844021e237c0d30f3604a2bc6306",
+  "songs/all_of_me_vocal.pages/0007.png": "ecdad2ac3c0a38bb0a553986b68fd64b6bce4dae7e2e654c5a152bc83abc61b9",
+  "songs/all_of_me_vocal.pages/0008.png": "0e619566374434cae278bd66344d94c80507e7477f678172da1f1cdf24bb65b9",
+  "songs/all_of_me_vocal.pages/0009.png": "8ef33bc47271fe389b3cc1c03be11e8689e8f5d1e3638a8af127adecbe90cde2",
+  "songs/all_of_me_vocal.pages/0010.png": "5f40610e4d3b143d3260b574c28c633b3a18e6e298fb3afe8adac95878bde3f7",
+  "songs/all_of_me_vocal.pages/0011.png": "32c857d8cdac61f34eb97031e27dce2f3b7d85f354e002c76c6947c07a49fb48",
+  "songs/all_of_me_vocal.pages/0012.png": "f6674afe2c6f4ead074491509ff12fc572656a73d894b170a7ef78ea0f83adce",
+  "songs/all_of_me_vocal.pages/0013.png": "886cee78fa1a4f5868a6adba5205d0843a6b9de0af42ea80e047c514b6ba0bc4",
+  "songs/all_of_me_vocal.pages/0014.png": "0e7d208b5da11cf6fd25b499ee138d865e63e85e2d9392ea9363623145b5677b",
+  "songs/all_of_me_vocal.pages/0015.png": "ba792e980325d694638ff90c7e9b87713de6b313c8ca2667e2889cd278581c42",
+  "songs/all_of_me_vocal.pages/playback-0002.png": "ad7fc6426e39e204109e3122bfa142d203abe60ba76a59b4df507e61745d923a",
+  "songs/all_of_me_vocal.pages/playback-0003.png": "4980352dee0600cad30f54ffba81577f4285248c7987df23aaa84f28544d02ed",
+  "songs/all_of_me_vocal.pages/playback-0004.png": "ad23b22d0fb931f098b88124fb6e48d2a1b03437f12944d8dbfbab9e5a6639e1",
+  "songs/all_of_me_vocal.pages/playback-0005.png": "065262ff6b758419107fd41f7b3956d996c325d6552a72f62281288c57ed29c1",
+  "songs/all_of_me_vocal.pages/playback-0006.png": "bd6cff39e52a41aab31473740a77357c47b2bb2b3dff42cfa794d3fe7888d7c1",
+  "songs/all_of_me_vocal.pages/playback-0007.png": "7cf0ebec216da49ab7385514a10e466656770d6668975840c8967f132414d2ce",
+  "songs/all_of_me_vocal.pages/playback-0008.png": "b4d59c19612d34d766cf2d76db71c6d6238d9afd6ce88f51dfebd117e6b1c5e1",
+  "songs/all_of_me_vocal.pages/playback-0009.png": "3d30c0180874fee2163821c4ef160cc5e134e5c5069f6e77ba542e40f5174bde",
+  "songs/all_of_me_vocal.pages/playback-0010.png": "5464485dc6c19973ac39dd3e573b9d7884cae22a6ef632f3c31e0e863635c7d6",
+  "songs/all_of_me_vocal.pages/playback-0011.png": "761aa1f8a8096046dabef1c1a30875205aec3309030cd60ae27938f51247f154",
+  "songs/all_of_me_vocal.pages/playback-0012.png": "0285ff0feffa0a61ec1a26b3eea54ca9156cba357847c74b1cfeac2084d454f4",
+  "songs/all_of_me_vocal.pages/playback-0013.png": "6177b132b398724081c814a65006ec205df52ea90403ed0c543e6ac9bdfdf2e8",
+  "songs/all_of_me_vocal.pages/playback-0014.png": "5fb997b60b54f808490b9fa0c6fedc396540f3b407c33b4562b54290daca4afe",
+  "songs/all_of_me_vocal.pages/playback-0015.png": "2a4a6345c63a9e6548519a3303d369bff76896eb1c4bfb40da42dc29fe08f710",
+  "songs/all_of_me_vocal.pages/playback-0016.png": "2ce1db668951fa36a075f119a423b1f50a1c4f346a29b1077cd55ecb31a5fa7b",
+  "songs/all_of_me_vocal.pages/playback-0017.png": "9f2677349e9d54f8de873e12399fb1f30a24d18e5f06c990aea2190cc41737e3",
+  "songs/all_of_me_vocal.pages/playback-0018.png": "25e7ab38426b3ce2c970c0c474aac7758f0f8c6a816fd0472a1a98ae4e37df9f",
+  "songs/all_of_me_vocal.pages/playback-0019.png": "f580eb1801c2ffad826c48a5a3c0b35c7513a8e4949723bba3f8f4522d03534e",
+  "songs/all_of_me_vocal.pages/playback-0020.png": "e6f23793d569cab0069560e88b1bc38e8fe44b1a11843d3a1a7639a33a6ab2fd",
+  "songs/all_of_me_vocal.pages/playback-0021.png": "a3cd07885f5ec333ba7ab3bf61807cb66263b7a4da4f1cc53e36717388a0cc13",
+  "songs/all_of_me_vocal.pages/playback-0022.png": "82529db7c06aa1ebe3bf5608287d2f4a6822337a5e1261d4687a6a9665478efc",
+  "songs/all_of_me_vocal.pages/playback-0023.png": "0b2c34c2524e5d437187d4bbf5cda395c55149081cc1478405a338d29af02ee3",
+  "songs/all_of_me_vocal.pages/playback-0024.png": "08d783cfb2d4bc09e83f3647a86455394f044dcce723ab9c5fa55063b222e844",
+  "songs/all_of_me_vocal.pages/playback-0025.png": "9c65d79d14f04bf05bee9de69c6c37a871e50aab635de797a91eb62fd81aac31",
+  "songs/all_of_me_vocal.pages/playback-0026.png": "79e87e2185d99c32aa753ac54068fabb698f81b16d6017ee7285f3b7c4d20054",
+  "songs/all_of_me_vocal.pages/playback-0027.png": "015cd105d6e5d2130393ced1268413b4929ff77231c30501b3a2748be6783b45",
+  "songs/all_of_me_vocal.pages/playback-0028.png": "7f3f16ced98698ef1034101976c05a1fb33b7c513057066b160b42eefacdbe64",
+  "songs/all_of_me_vocal.pages/playback-0029.png": "dfe0f2ea02945997653b0fac1b6d1355cd1c9a2cb5307f38ee59d51a54d4ec53",
+  "songs/all_of_me_vocal.pages/playback-0030.png": "98e2a6862eff212591ffc51d55c48ab65267e670bdb56d6c7ca6fb00ad750086",
+  "songs/autumn_leaves_acoustic.json": "e07a7e4fec89c811e6c26c1bba64af690743662074faa6b8f0fc81288097b53f",
+  "songs/autumn_leaves_acoustic.pages/0001.png": "54cbffc07ff6a31d8c340a4acaa14e6818b50b08d60041d7aa409fed01c2864c",
+  "songs/autumn_leaves_acoustic.pages/0002.png": "563ffa15c52a986603a17596e3ae9177bfc5222910a5c5bf31cbf61cdd1845fe",
+  "songs/autumn_leaves_acoustic.pages/0003.png": "fad7549f767ab0b261e58266ef9d6f227f5fe8d90f5c1ebcb8ecf1b0fee790a2",
+  "songs/autumn_leaves_acoustic.pages/0004.png": "fb5b442534e05f2fa9729965d0a05acc9c2d2878b9af297b6d646d7f625dd1e2",
+  "songs/autumn_leaves_acoustic.pages/0005.png": "a32a12e59624f65cf30685c5f4439514575d54fff42243506278b68b4961199c",
+  "songs/autumn_leaves_acoustic.pages/0006.png": "749df9fa3bf3bed1033b7a9950755f64e19e9793da91f35fa95e44da85d7dd4d",
+  "songs/autumn_leaves_acoustic.pages/0007.png": "e90ab72d11b381e70b11c987532ab25d84518d272fb7b03517d25a1f952aba6a",
+  "songs/autumn_leaves_acoustic.pages/0008.png": "846f529b487a4df90f8041d0c893225e8b3cf71feb1bd8ee903fd3a31126b8ef",
+  "songs/autumn_leaves_acoustic.pages/0009.png": "e8ac60d749ee6e1be2bd40457be800927eb8a321d11b2b98e663ef3835d2e8bd",
+  "songs/autumn_leaves_acoustic.pages/0010.png": "694c524e7cfc5b23e0fd8a301c230f7871bb783ad5243b7d45f34101a2ea22ae",
+  "songs/autumn_leaves_acoustic.pages/0011.png": "25e7b830b5fe8b9c9aaab2d31ab713a1b8da720f2ed116c547162ad77b99c10c",
+  "songs/autumn_leaves_acoustic.pages/0012.png": "afb17b0fae1be9504395a497776033736d7eccb8b040061333bdfe456035acb5",
+  "songs/autumn_leaves_acoustic.pages/0013.png": "76bd3e7c8a6c3a95a98f8c96e521509bc3ff4563fd5446032939e7c2c577f21d",
+  "songs/autumn_leaves_acoustic.pages/0014.png": "9701a0f3d5f5a3f32fb18ff1c11c5cc525961a9a9416c98b83818ff4607afb37",
+  "songs/autumn_leaves_acoustic.pages/0015.png": "235584fcf484de70f3beb463d1eb3783ed20d6c296eacd1fb8a5b9b3127eccab",
+  "songs/autumn_leaves_acoustic.pages/0016.png": "fe7ce9c311c2f57e9b6cb10fb5ca01f7f103d0d0f29e4da806e96b6cc6e005a9",
+  "songs/autumn_leaves_acoustic.pages/0017.png": "639450b174f68900a71cbbd3ab8a66b621f239e07922673e9482e49f30a892a0",
+  "songs/autumn_leaves_acoustic.pages/0018.png": "c15b4d2cfa76bebc9866dd022527999b0e7a09726738a7da6ba2285c7c4d9420",
+  "songs/autumn_leaves_acoustic.pages/0019.png": "84f637a60432cc35981a895899993b9b1b9f35a6ea6d211bb4aa95ccaeb42d8c",
+  "songs/autumn_leaves_acoustic.pages/0020.png": "e20b7a45b003e68b0f890b263f06adbcda947c3ecada541c2f0feb9dc9424741",
+  "songs/autumn_leaves_acoustic.pages/0021.png": "1651902b453243d5bd7fbc203417d232398063d2161eae37dfaba9327a3d35ad",
+  "songs/autumn_leaves_acoustic.pages/0022.png": "3051d9af506ddc661b259f2ca5c9f2d80076b1e9d6e303f38970091958f48bf0",
+  "songs/autumn_leaves_acoustic.pages/0023.png": "7c554926f10ee5090bde0da5f182f965cf8650889f8a3d6227334006ba65ec8c",
+  "songs/autumn_leaves_acoustic.pages/0024.png": "ead80368cefbb664988df29571cc3ac68a4ec599d70f0c53d628715e9795fc1b",
+  "songs/autumn_leaves_acoustic.pages/0025.png": "953fabb18457d14a5797ad5a6fd5ce0f3af099bb3877f08fd2813fdeca7e2481",
+  "songs/autumn_leaves_acoustic.pages/0026.png": "13da788d7bcce194552854ebdbb1601d5322bed6ac0bbae09e3cc07c34610379",
+  "songs/autumn_leaves_acoustic.pages/0027.png": "bbc81588269392772e6ae2671289716e1f1b51cfe8ebb790e887e866e465a7a7",
+  "songs/autumn_leaves_acoustic.pages/0028.png": "109adbfb7abf9059d198ce6abe1612457f6f0674636219ab33ba109e89fb8ef5",
+  "songs/autumn_leaves_acoustic.pages/0029.png": "1052f1b8e1e7746fc846c6893a02e587b0b204f32d8307800d7fd74ac06383ca",
+  "songs/autumn_leaves_acoustic.pages/playback-0002.png": "e82e130512e34e2801d39a730d4acac3ca689e0736ab100770d49404a598d034",
+  "songs/autumn_leaves_acoustic.pages/playback-0003.png": "5ba697f7f059b627dd4467589c4f4891413cbf7ad85932800a7fc00c7c70255a",
+  "songs/autumn_leaves_acoustic.pages/playback-0004.png": "f1bb58fce2cdcffa5523ac60099b6e52c356c6696fc1a4ff60a5cccd2dd3ee1e",
+  "songs/autumn_leaves_acoustic.pages/playback-0005.png": "15645d74bb6ab75901e87485dbcfc2c797e8a79b03973c1e1708889be2fc68c8",
+  "songs/autumn_leaves_acoustic.pages/playback-0006.png": "724eaab2251f9b799a439fb0fab1cb200ca471ee8a7e13718167e0de7481e20c",
+  "songs/autumn_leaves_acoustic.pages/playback-0007.png": "b1043e1876883e3d380cf8e3a59b2f6850d48054e9d0e570ca1eb988f3b78cf1",
+  "songs/autumn_leaves_acoustic.pages/playback-0008.png": "e5529398605d81e4265239afc5b6117bf0e89743fa2662d9edc4c8a1a71dba3b",
+  "songs/autumn_leaves_acoustic.pages/playback-0009.png": "690e52975aee8c6e21231e3d2e8be84fcb15fd42134bbb69c8bdccc3e8c8be7a",
+  "songs/autumn_leaves_acoustic.pages/playback-0010.png": "fb950d14561f570f1f645903cd4bce289bac97d182a237b1d26d3ca4c1e40357",
+  "songs/autumn_leaves_acoustic.pages/playback-0011.png": "3c6d7cb9269f25fd89feaac66eb14c4e1c5f40b1c1e5b4a11cd9993e90d70180",
+  "songs/autumn_leaves_acoustic.pages/playback-0012.png": "b317e5306a4f8ab59bfd21688640aa02df31382dcadbaaeac016e8682d4a95fd",
+  "songs/autumn_leaves_acoustic.pages/playback-0013.png": "b0949d15a05cb2458fd2fa5f6f842855591ddcea8caa260ce3006d849a7b3498",
+  "songs/autumn_leaves_acoustic.pages/playback-0014.png": "676df949c9074b9f096f1ec8535ff78a8852020a23ba50055bf95e4a03515771",
+  "songs/autumn_leaves_acoustic.pages/playback-0015.png": "1da00065ad926e8e46ff475f1db3a21d1beb1b7d021fe1e899e1ceb330dd6a6e",
+  "songs/autumn_leaves_acoustic.pages/playback-0016.png": "62504e382dee30dbb52e999c70bb4cd7619412cdd4304deb619527f5e81e03db",
+  "songs/autumn_leaves_acoustic.pages/playback-0017.png": "4f30f876ad7bec3f1a7962838b9431b640a1cd663421068e8d31400c4123b1c5",
+  "songs/autumn_leaves_acoustic.pages/playback-0018.png": "af9ddd4d84fddf1356ae21ca5f54f74011bbc7860b6ca34094daba6f0374ae8f",
+  "songs/autumn_leaves_acoustic.pages/playback-0019.png": "b46f18b2e4dcd8272f6b97a4599787e16a94afdd78adcb3c697cbc415573d861",
+  "songs/autumn_leaves_acoustic.pages/playback-0020.png": "6c84621d515f3fa2b6b5ddedb4c7d7a28e1f7916ab86241a27aed3e5e0036c97",
+  "songs/autumn_leaves_acoustic.pages/playback-0021.png": "9a95f5db7d7350cd5dd1b81408c65395826329eb0f2e95d0f12d93f281e7cf69",
+  "songs/autumn_leaves_acoustic.pages/playback-0022.png": "9c41ee3793c44018873ffbc0847e001a2d2a7273ae487b1d8f47a7ec10b1c51e",
+  "songs/autumn_leaves_acoustic.pages/playback-0023.png": "213ee4b1ed54411d16c880907b0d4d6c04ba9f97bed9eec4e4c5a09067040987",
+  "songs/autumn_leaves_acoustic.pages/playback-0024.png": "b37549829a19c82c525d4b2710b6ad0db21f7ca9735b71817e6e06de826796c9",
+  "songs/autumn_leaves_acoustic.pages/playback-0025.png": "950f311dad81dcaff3b6d73128c2869ab6d7277b7bac4358599d9bad3fe07147",
+  "songs/autumn_leaves_acoustic.pages/playback-0026.png": "6495623d373cf5d464c01e8a3c7f6e95984af75fc8ba6370fe72bba2a9c5a1d2",
+  "songs/autumn_leaves_acoustic.pages/playback-0027.png": "36e1a9c2df257d706af5f319c4616dfc9bcd6aab587f97bedcb4a1e8594a524d",
+  "songs/autumn_leaves_acoustic.pages/playback-0028.png": "e732e810da00f84bf74fe2f26d57b2fae01ea4691c39bf17cfc89b7707672716",
+  "songs/autumn_leaves_acoustic.pages/playback-0029.png": "01da01ecae8bcdaad33240fe686b2f44604a40ed5979cd5bb0aa4481035c9f11",
+  "songs/autumn_leaves_acoustic.pages/playback-0030.png": "52d1acf4d3cc5bc531ca879e9d47281d72dafb8079dca349bd12965528ecba52",
+  "songs/autumn_leaves_acoustic.pages/playback-0031.png": "e0c220f7f8522679bf628b03ce472b03340b8951f4be5010952822fcad8f6bd2",
+  "songs/autumn_leaves_acoustic.pages/playback-0032.png": "42801ea8c17bc1f49689a6ca7379928dfb1e569ee7354a014451ded48112bc5c",
+  "songs/autumn_leaves_acoustic.pages/playback-0033.png": "e447393a28aad3360e02dd4fdd6886eff73a46503f94511056938f68e629e13e",
+  "songs/autumn_leaves_acoustic.pages/playback-0034.png": "0b490c24ccba2e1d43649e64d21e48b1dea2f34f91d2e459d850bb02a4fd5e17",
+  "songs/autumn_leaves_acoustic.pages/playback-0035.png": "079872d5fb0bde62bc41909ca74246ed9804c6d46e8bef78185fffd6f41fd33a",
+  "songs/autumn_leaves_acoustic.pages/playback-0036.png": "6b90cb2c9cf07e7e5896cb57961cba6de2c5cb226772e0ad67ca75caab34dc3d",
+  "songs/autumn_leaves_acoustic.pages/playback-0037.png": "d5d2d73bfac0ad110ac55c54e87bd63a26799d14af76fe20378100e72b715782",
+  "songs/autumn_leaves_acoustic.pages/playback-0038.png": "7ee879807b0e1371326ea4cfd38ba59218c649397ef1448589f0a4b0557b9b85",
+  "songs/autumn_leaves_acoustic.pages/playback-0039.png": "9566293d49f978823df090545d7239172ce836b54d0a184c2f50672509f5095a",
+  "songs/autumn_leaves_acoustic.pages/playback-0040.png": "f4a68c14292b2c8cf1b870f0f5ea74603439a20317c931435b94bf4d69b6c7ba",
+  "songs/autumn_leaves_acoustic.pages/playback-0041.png": "d899bd39cc713bbda7c521537d81c775b609e02df199d4b740eace1a948cb27e",
+  "songs/autumn_leaves_acoustic.pages/playback-0042.png": "e6f07ad76a91f5a0a1c563a238e5f859fd0d8799d18e429ebc6967c1c391ae0e",
+  "songs/autumn_leaves_acoustic.pages/playback-0043.png": "9b0cd3c1bce012b04afe478cbeba630643de02d695324c42f2062c515efb7321",
+  "songs/autumn_leaves_acoustic.pages/playback-0044.png": "1eca5856dbd1f7c58297b9e47766675efa44fabbbbf5668d07dede8d47c2bdea",
+  "songs/autumn_leaves_acoustic.pages/playback-0045.png": "d9eaf533b05d3a889bba6005f1cef1c1b62466db18aa7bac819f5ba2b25d27e7",
+  "songs/autumn_leaves_acoustic.pages/playback-0046.png": "8019f806b1782995ad79a2f06463e0241c3442195ba9cbc3f6a0c2719c3afa85",
+  "songs/autumn_leaves_acoustic.pages/playback-0047.png": "b0384920846c4089363ef8cfa4a5ce70fc2562788592a06138282b4c019da225",
+  "songs/autumn_leaves_acoustic.pages/playback-0048.png": "b7a7489c6ef5744c5daa995600896dd2694eeab383f878a02dc7057e530d657e",
+  "songs/autumn_leaves_acoustic.pages/playback-0049.png": "c76ff27923d2908a30e1eea6d880064de7e7c941814608452c3b8dd594daf850",
+  "songs/autumn_leaves_acoustic.pages/playback-0050.png": "ff9d2e94684c7b0342f6b9833c8e7e3c5611be9a436e8fd403d809c8540f8ed5",
+  "songs/autumn_leaves_acoustic.pages/playback-0051.png": "f376a335fe15961cee9781f8ea53307b3f6578a06b194f3304e4704278e5defb",
+  "songs/autumn_leaves_acoustic.pages/playback-0052.png": "8be1c27434d95f231ddad913981f140a3df9beb4914ca6e4d1e4a5dc42a65798",
+  "songs/autumn_leaves_acoustic.pages/playback-0053.png": "7261e3d2465bf7d4de7b7710aff229d64b61cf3861870cc6aeda931d88d602b3",
+  "songs/autumn_leaves_acoustic.pages/playback-0054.png": "51375ba98654c3ddf198dd4da24c72b688b37f6c3670fd0eb77ffa5fdabb3965",
+  "songs/autumn_leaves_acoustic.pages/playback-0055.png": "c2e8d36d522a39131eff7af3cfabc8139baa90ca55d1e523aa6cb2590be933c6",
+  "songs/autumn_leaves_acoustic.pages/playback-0056.png": "2d4c1e0611eb4c4d2e653e25f4719f4da8ae93b4d481e22bc401f615cd04093e",
+  "songs/autumn_leaves_acoustic.pages/playback-0057.png": "d15d0441b80e087fc3d8f01dd7086a6fcad5ec6c66df3ee410920ddf8e8172fc",
+  "songs/autumn_leaves_electric.json": "90250a7776c295c4886c1cad6aaa0ee5f42430e9309289fdc35b8a99ec0e1de3",
+  "songs/autumn_leaves_electric.pages/0001.png": "6a10d99239f2a2f7cb86f10a371410191e8eab0d7335ac96f382efb7ebc8be73",
+  "songs/autumn_leaves_electric.pages/0002.png": "6ab880d8341c5ee92fece84d0756f942bd12e4f80cef6648f3ed779d386a93b5",
+  "songs/autumn_leaves_electric.pages/0003.png": "26e73ccda608f5baebec6e9c1beceb5586b13b5d138f0d29d4c13f58a6924715",
+  "songs/autumn_leaves_electric.pages/0004.png": "d7d47739c2c32a676198d091d546e027e218530dbe76147a71ad7156dad96f8c",
+  "songs/autumn_leaves_electric.pages/0005.png": "3c190110e3b59e42185dedcd4351e36f90d6e79788732f91b55fc92e059053ab",
+  "songs/autumn_leaves_electric.pages/0006.png": "39ce5045c8bb217a3b8820d4a1af14896faf313ca91ebe63ff848eba6c76e0fc",
+  "songs/autumn_leaves_electric.pages/0007.png": "1f5f36692863b4ccc4f08cf3a8b9c2c8edbd9f5b72d8ee76aae78dee8fb5220f",
+  "songs/autumn_leaves_electric.pages/0008.png": "52e12ff6e4983451ad7e59c45f3c5cd049171e00f2c19ce40e10de994764cbb7",
+  "songs/autumn_leaves_electric.pages/0009.png": "eb18d7f17fd0a101ae02df700409f7064cdc1ed585f315dcc25220490a3a3ca4",
+  "songs/autumn_leaves_electric.pages/0010.png": "8b923a580500ec4dddfba53ac57029806acc34f4bc51045296d46ba9db9fe0b8",
+  "songs/autumn_leaves_electric.pages/0011.png": "ceafe100023db75a8d34ea08e8c66155ba76aa12e8a24c9b83294d2a01779ca9",
+  "songs/autumn_leaves_electric.pages/0012.png": "813635f070252ce2cfa76de28fdb7badca2534783edfd7d791983d8b22d05b20",
+  "songs/autumn_leaves_electric.pages/0013.png": "e828faeb75fa104b6e15991e0489db7a43652bbde47ebcf818348a54614d5452",
+  "songs/autumn_leaves_electric.pages/0014.png": "6bcff78f5fcd2b214795e1463cda7f817785f2cd80c9727147ea12fe169760cf",
+  "songs/autumn_leaves_electric.pages/0015.png": "19bde11ca45dd5927797ee23a8cdcbfc891e7ff29bc9a01c2ca945b84e07e5e8",
+  "songs/autumn_leaves_electric.pages/0016.png": "071a61fa83944bea0b04aa221b19d124876c2a5f1b1e8347b8edaed4ed1aae92",
+  "songs/autumn_leaves_electric.pages/0017.png": "1d1ecbdf8e123aa2d003e352e85070eaa8b20979dbe25ea04be61f9fb8efccd0",
+  "songs/autumn_leaves_electric.pages/0018.png": "d551633f1c99dbe7b74e2fb2c2c7ef490eceee0d812cf697702de2077c2b74b7",
+  "songs/autumn_leaves_electric.pages/0019.png": "71672fc8613539914aa4069a4668751363e0be3d2e9822cf078755fa6b9116f3",
+  "songs/autumn_leaves_electric.pages/0020.png": "86747ada8e9ff0b1c05824d1a1ec9328f01cf33a65c3ae13c64a1e075c0a52ba",
+  "songs/autumn_leaves_electric.pages/0021.png": "c981fe628c1621c6f5add8635e33aaacae112fe954b2b43f15b3f02604c6c9e9",
+  "songs/autumn_leaves_electric.pages/playback-0002.png": "53f34213f307f1c7ab471c3c28db34a28e551936989b1a450282a325b533b71d",
+  "songs/autumn_leaves_electric.pages/playback-0003.png": "33f686464316f82a30d2b71bbafb6f8d2a74c44461f9b6b2c4754632671c4381",
+  "songs/autumn_leaves_electric.pages/playback-0004.png": "d99dcc2f8f15f120c2bf3cc6eba91b794aa57cd0078961d930ffc8dae843c791",
+  "songs/autumn_leaves_electric.pages/playback-0005.png": "568f242912b71a2a0e6b438fabaeaf043a62087d1b3018d61838093e6812c392",
+  "songs/autumn_leaves_electric.pages/playback-0006.png": "dc5b754b3d11d136a89c82b3160b3cb631572065505b2770f529c312c8beb0cc",
+  "songs/autumn_leaves_electric.pages/playback-0007.png": "13d877cc54210a860f0e08006c5e386a6a3e5c339e2d334df11ad37afd8b8fec",
+  "songs/autumn_leaves_electric.pages/playback-0008.png": "90c1df01c76f8c919cfd7276f80a899259851e090975ea1d1cabdcc613d02d72",
+  "songs/autumn_leaves_electric.pages/playback-0009.png": "dc2be361fa7c0c2c56fe02c24a97bcb628a1eff960e8b1db78739679f562759e",
+  "songs/autumn_leaves_electric.pages/playback-0010.png": "07d5c2b2ae31ebd88d4fb4708caefac36aca5d436048c1ffad55feffa6d87925",
+  "songs/autumn_leaves_electric.pages/playback-0011.png": "8d22eb7cc86906c36967434e31811a4542b1e44f6590eabff23f9a940916d207",
+  "songs/autumn_leaves_electric.pages/playback-0012.png": "c964863cbd956968210fc939b75ef6681d6f797f50860b75d8b7d0736ca12305",
+  "songs/autumn_leaves_electric.pages/playback-0013.png": "7d9c22406e24aff928e56cbebbb4749d1e8880542975fd53447afaca19b44584",
+  "songs/autumn_leaves_electric.pages/playback-0014.png": "2fce4a9c3624e90ebf964965a11d37e951db7e18824a2268c487abe2dd414168",
+  "songs/autumn_leaves_electric.pages/playback-0015.png": "edda9e50c852a5da934c21cd2d8a70a19e8c54b9c7020feb0d542ed0b257c2b7",
+  "songs/autumn_leaves_electric.pages/playback-0016.png": "50cba6043f888330d3a01ecd695de8f3ed7f3e51ae94da54b3faadb1088e74de",
+  "songs/autumn_leaves_electric.pages/playback-0017.png": "7c8bcaccb8b7879665b50a1185a90cc3ee31e6bcd21ecc2fed2dcd723d31e114",
+  "songs/autumn_leaves_electric.pages/playback-0018.png": "084a522a8e146a7fe533b3498eb842a586cf743c6a034b79f15b067a6ce52a4e",
+  "songs/autumn_leaves_electric.pages/playback-0019.png": "9f47a55406500ef63d7936065fd53685cef4d72b7b2190a14e6daf28e4d8bbbd",
+  "songs/autumn_leaves_electric.pages/playback-0020.png": "95a7d3e90b7a7cf435ce87c1d83366822f38f53857d993cb9c242afce3f1ac2a",
+  "songs/autumn_leaves_electric.pages/playback-0021.png": "f983e3bccc183efa8fbbe9f83a7629b056820d15129bc84108f02934a4b52ae3",
+  "songs/autumn_leaves_electric.pages/playback-0022.png": "614a51979fa8c9229503018645533118f05f496ffee4be4003e18a2281015844",
+  "songs/autumn_leaves_electric.pages/playback-0023.png": "223fcf58efd3e678fd0e5a761a2f504eea569a1cb4f6b27f85baa8d425bdb499",
+  "songs/autumn_leaves_electric.pages/playback-0024.png": "8c3ef22114aa00a42f603daac996f923d3d4aef9ee1cfdd2daa437a8760a9c85",
+  "songs/autumn_leaves_electric.pages/playback-0025.png": "ba7d51c2f2eeeefa52099d2401d695ccdf3091a49599c206eaa1daa39c68eccf",
+  "songs/autumn_leaves_electric.pages/playback-0026.png": "9c09778168a6b0b44d3beedb49c915a9e126fe47e8ec0afd4e72061ebadae533",
+  "songs/autumn_leaves_electric.pages/playback-0027.png": "53f851a9583415aa36f60aa4655f04d92e38cc3a679d9205bd93fbc971798e41",
+  "songs/autumn_leaves_electric.pages/playback-0028.png": "591e475f21cf481cb35278ee065cd808fa141162320d54c1ad589d8ff692143e",
+  "songs/autumn_leaves_electric.pages/playback-0029.png": "01fe5d38ca9867a442696e3332fb1a5c11ffadcd1e1182ed6164f6caae1c7950",
+  "songs/autumn_leaves_electric.pages/playback-0030.png": "6cc22a97e81be03b6eef0ef11b0cf8d088336eb19da26a8bb4e366c3615145db",
+  "songs/autumn_leaves_electric.pages/playback-0031.png": "93a7835d071c07c17d9b3fc50e1e2ff3b19d0b3087f21ef19c18bc622519ded6",
+  "songs/autumn_leaves_electric.pages/playback-0032.png": "ffdd2864d336f12375e963cb0fd4647992b790d92899f809a17f0aa2941b9324",
+  "songs/autumn_leaves_electric.pages/playback-0033.png": "8c2097ce48fb79c218aeeda3513025d3c6c3488aaf4682c672cf703f05366b74",
+  "songs/autumn_leaves_electric.pages/playback-0034.png": "07192aa9420386cb8165b1f43be384b83a7b588b383e57d3905b235acf52d77b",
+  "songs/autumn_leaves_electric.pages/playback-0035.png": "786e44c54bdb27b095dff2f903df5319e794355f986a2ed86882de78e299b589",
+  "songs/autumn_leaves_electric.pages/playback-0036.png": "f4d8b82bda3c599dd803b66a5ef1d7ef77f57d5757dafcda168caba6fb8a0399",
+  "songs/autumn_leaves_electric.pages/playback-0037.png": "d3e999968b05cb703fba44bcb1f3b8cc1b0934ca7513f9e952db41a27d9dbccd",
+  "songs/autumn_leaves_electric.pages/playback-0038.png": "43773db6f940cdd5457053e9d1cebb1f715d7a9d069fef8f29dd280bc664383f",
+  "songs/autumn_leaves_electric.pages/playback-0039.png": "da683c3e3d6198a49464d6e9463f9bed2ad9595c6c69ac09adaeeeeddb626003",
+  "songs/autumn_leaves_electric.pages/playback-0040.png": "1e1fe40450357ed40ab4a688906e62c69306dc706ec53e4c23de94d7228dffc3",
+  "songs/autumn_leaves_electric.pages/playback-0041.png": "f7c3ab577b12be529b9c73b44521852db930681e6dba1410aae569e526fc4a29",
+  "songs/autumn_leaves_electric.pages/playback-0042.png": "a827c32cf60d5bafb3b042d36f14883bee389e677091bfc5033771356c164254",
+  "songs/autumn_leaves_vocal.json": "412981cfd4ea208bbda8de8bbfc2d751164c379340bc02a61233692ef19f1032",
+  "songs/autumn_leaves_vocal.pages/0001.png": "4b9402563b8ae88a34f25482d5db3d5279643bed60731c7baac69a030b3ce2d9",
+  "songs/autumn_leaves_vocal.pages/0002.png": "b961fb05e5539ce4335b561df9fc9558b81574872a35956da0beb192a8db258e",
+  "songs/autumn_leaves_vocal.pages/0003.png": "a3e5423f083d8159e52dd4f1fa1532b982a4290dc3db75921a120fa3befb5c7d",
+  "songs/autumn_leaves_vocal.pages/0004.png": "9aecc0d1c84bdebdf214c99469ef2fbc7a8e625471b8b06e26c3267dea1dfc42",
+  "songs/autumn_leaves_vocal.pages/0005.png": "80f3956a196ef56b01647c7daa0d58989c12f04b2ddd8c166cedaf846c1d0f18",
+  "songs/autumn_leaves_vocal.pages/0006.png": "56e0fcb5faf8c5bd514efd6568284d6548708b4fed7d470c138d9478db34eb77",
+  "songs/autumn_leaves_vocal.pages/0007.png": "81b80d0a70883a69e10b8f06fd2c2f904670dc3a1cae13b980d239ae4a882e46",
+  "songs/autumn_leaves_vocal.pages/0008.png": "d55633751f78440bd94f1dbbed846c151cf79bebc5fa4b0f338add0c4b6d2e99",
+  "songs/autumn_leaves_vocal.pages/0009.png": "2da18b1db70f1cff719f697c39ecda329dbc60d3fe0d605351fcae8583e6901a",
+  "songs/autumn_leaves_vocal.pages/0010.png": "321d18c54e138248b31a00df6e3a95b9af62588a227a83e56db7475acb923d7a",
+  "songs/autumn_leaves_vocal.pages/0011.png": "c02c41a2ff2b14ec5bde44f22bec03fd71edf2d9e272d2ef0a8434b843a26b6b",
+  "songs/autumn_leaves_vocal.pages/0012.png": "ac4bf6573e196d5afbb0049bcc54836a7acac6a1e9e8cce48dedad203f4b43e0",
+  "songs/autumn_leaves_vocal.pages/0013.png": "6c22d2dde54e4e7d6cd4cef815ff4e4a9738cd48707f344e90e75737939f68ec",
+  "songs/autumn_leaves_vocal.pages/0014.png": "3b602afdbb2705281dc2dc5120427105649c5df1692155540c9ad9adae3621c8",
+  "songs/autumn_leaves_vocal.pages/0015.png": "59339718670a3c8d97b6efb7acc3e7234cb26b11e135da9f502689c77824be8a",
+  "songs/autumn_leaves_vocal.pages/playback-0002.png": "c95138bff07d8dae52535a96bb33cc3a31c6509d7da49c60c35a55f2a1072c4c",
+  "songs/autumn_leaves_vocal.pages/playback-0003.png": "fb030bc5b0aa831b534223b63b07cbadd7ab76ce9376c3bde8965f09e73d41f8",
+  "songs/autumn_leaves_vocal.pages/playback-0004.png": "250262570aac9adaff71ddde21a61c65550afb46849016dcd5162cfcedb522da",
+  "songs/autumn_leaves_vocal.pages/playback-0005.png": "4832b81482f73003ec7e2990f1558ac8d4cc62883ad1c01d8e78837a37a6de6c",
+  "songs/autumn_leaves_vocal.pages/playback-0006.png": "0b753c25706437aa8b716f9a254e5dfc03c0c441dd2dfc4f038c3fba7528dd19",
+  "songs/autumn_leaves_vocal.pages/playback-0007.png": "9f9cfa20a8dfa15cd5ac9e0c47f5d6c0632177702229d5f5c7566c315aa99459",
+  "songs/autumn_leaves_vocal.pages/playback-0008.png": "d525a0af7688927b7cb5f14302ab7151b9e2d0dd83d04d4b53ac7414f8c928e4",
+  "songs/autumn_leaves_vocal.pages/playback-0009.png": "f6dbfeca5e20dcf475f8da0285632b317759e1d2d4d69a54a4232d853db68004",
+  "songs/autumn_leaves_vocal.pages/playback-0010.png": "b54d909532c99f359dded5fc2cb11f93309bd8a158b500ee3be524338e471f48",
+  "songs/autumn_leaves_vocal.pages/playback-0011.png": "619b4621c5ade46fd29e5e70f08c8d421e1916e0578fa2979bcb4a8204dd99d7",
+  "songs/autumn_leaves_vocal.pages/playback-0012.png": "4472606d66ca6d1a6d490e89f127327e121331eba14c89b1f20e108ed63cb2af",
+  "songs/autumn_leaves_vocal.pages/playback-0013.png": "525be592c83a6a119c1b2bc8f0eba24de0bac7ac66c56899f10921e959ae7290",
+  "songs/autumn_leaves_vocal.pages/playback-0014.png": "8f792dd41bad096867edf9e51fcbe5e6773db1256e849cc32b9402aed59ca991",
+  "songs/autumn_leaves_vocal.pages/playback-0015.png": "2767f2d9979040258f3a619274e6f11fc8e750b7dc3f0d34adbf373455c08200",
+  "songs/autumn_leaves_vocal.pages/playback-0016.png": "8a61095e966c67c35df99da5fe32d0bb710c9e0443f135585593100a3b76a8bd",
+  "songs/autumn_leaves_vocal.pages/playback-0017.png": "234f9045d2cc31fc73f1c11bed69641acc5887ac794d051760ba041df5279b8f",
+  "songs/autumn_leaves_vocal.pages/playback-0018.png": "6d3156bc58fbcd88abc9c5b18e41ab62a7fece8996655c6723a52501869a60a3",
+  "songs/autumn_leaves_vocal.pages/playback-0019.png": "9851262495f7b0916982a8f46421948068d4208af9ec1d7ff22fd38a80860d24",
+  "songs/autumn_leaves_vocal.pages/playback-0020.png": "03026a3ab967ac2c963336c475f9ecb3033c799ae28d9e832a2e9d3ac5367c99",
+  "songs/autumn_leaves_vocal.pages/playback-0021.png": "d72cd7ed7c58cd4fd44372f6dfcef7e91b84b3c74f747bf1fc84a2c81c44da36",
+  "songs/autumn_leaves_vocal.pages/playback-0022.png": "46ff7fd7202c1378a9598982379d4d7322f5de934280a78eb5cd76a14f6fad35",
+  "songs/autumn_leaves_vocal.pages/playback-0023.png": "406830c4e11ecc52774bf67351a2d6c3410f2606df206c43cafa44c5beed42cf",
+  "songs/autumn_leaves_vocal.pages/playback-0024.png": "072dda94b8a251c775663f81b4b264edac9bdb64c67d115fd87ae469eb7b812f",
+  "songs/autumn_leaves_vocal.pages/playback-0025.png": "b98a8b5879620dfe0bccd063f8d6122fc6826b86b11d07da3aa7abb8a07f265d",
+  "songs/autumn_leaves_vocal.pages/playback-0026.png": "476255d5814bba2f838f9addc852f080408c24fa3d1c2b549c93da3d59bc11bb",
+  "songs/autumn_leaves_vocal.pages/playback-0027.png": "0678a2cf026519a06e62c8ef3599a429290092968785e71431584634bba26375",
+  "songs/autumn_leaves_vocal.pages/playback-0028.png": "d89db0cd8a2435a978a2e11b070c7aaacb3f791542aed8da4b3e17af888ceee5",
+  "songs/autumn_leaves_vocal.pages/playback-0029.png": "b8ae37ad031080e1a70f8113123e6706455798e51e8dae87913381f846661e08",
+  "songs/autumn_leaves_vocal.pages/playback-0030.png": "c04d59f0f791b9d813ba659fdb4bd616b649afca3a79b9ed437781f2301f04d8",
+  "sounds/beat1.wav": "634e73055b4ae05857de54c0cff0bee2ac4476dcde874b474b192512ba113a39",
+  "sounds/beat2.wav": "9bc510822228479fe4d4fd85be0d3b2f9eac009449f7fd6f916dd54661124c34"
+}
diff --git a/tests/fixtures/role_outputs.json b/tests/fixtures/role_outputs.json
new file mode 100644
index 0000000..c1e8da8
--- /dev/null
+++ b/tests/fixtures/role_outputs.json
@@ -0,0 +1,16725 @@
+{
+  "acoustic_accompaniment": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "acoustic",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_acoustic",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_1_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n1_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_1_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_1_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n3_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_1_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_1_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_2_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_2_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_2_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n3_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_2_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_2_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_3_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n1_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_3_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_3_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n3_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_3_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_3_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_4_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_4_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_4_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n3_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_4_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_4_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_5_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n1_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_5_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_5_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n3_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_5_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_5_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_6_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_6_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_6_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n3_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_6_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_6_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_7_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_9_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n1_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_9_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_9_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n3_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_9_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_9_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_10_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_10_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_10_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n3_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_10_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_10_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_11_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n1_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_11_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_11_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n3_p3",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_11_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_11_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_12_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_12_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_12_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n3_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n3_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n3_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_accompaniment_measure_12_n3_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_12_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_accompaniment_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_accompaniment_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_13_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_13_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "tie_to": "acoustic_accompaniment_measure_14_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_13_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_to": "acoustic_accompaniment_measure_14_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_13_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_to": "acoustic_accompaniment_measure_14_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_13_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_to": "acoustic_accompaniment_measure_14_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "acoustic_accompaniment_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_14_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_14_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_13_n1_p1",
+                        "tie_to": "acoustic_accompaniment_measure_15_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_14_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_13_n1_p2",
+                        "tie_to": "acoustic_accompaniment_measure_15_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_14_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_13_n1_p3",
+                        "tie_to": "acoustic_accompaniment_measure_15_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_14_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_13_n1_p4",
+                        "tie_to": "acoustic_accompaniment_measure_15_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "acoustic_accompaniment_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_accompaniment_measure_15_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_15_n1_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_14_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_15_n1_p2",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_14_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_15_n1_p3",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_14_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "acoustic_accompaniment_measure_15_n1_p4",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_from": "acoustic_accompaniment_measure_14_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Acoustic",
+        "octave_shifts": [],
+        "role": "guitar",
+        "tablature": true,
+        "tuplets": []
+      }
+    ]
+  },
+  "acoustic_solo": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "acoustic",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_acoustic",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_1_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_2_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_3_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_4_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_5_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_6_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_7_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "acoustic_solo_measure_7_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_7_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_solo_measure_7_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_7_n3",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_7_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_solo_measure_7_n4_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_solo_measure_8_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n3",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_solo_measure_8_n4_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n5",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n6",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "acoustic_solo_measure_8_n6_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 5
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_8_n7",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_9_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_10_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "acoustic_solo_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_11_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_12_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "acoustic_solo_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "acoustic_solo_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_13_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "acoustic_solo_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_14_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "acoustic_solo_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "acoustic_solo_measure_15_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Acoustic",
+        "octave_shifts": [],
+        "role": "guitar",
+        "tablature": true,
+        "tuplets": []
+      }
+    ]
+  },
+  "electric_accompaniment": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "electric",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_electric",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_1_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_2_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_3_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_3_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_3_n1_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_3_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_3_n1_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_3_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_3_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_3_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_3_n3_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_3_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_3_n3_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_3_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_4_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_4_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_4_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_4_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_4_n3_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_4_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_4_n3_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_4_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_5_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_6_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_7_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_7_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_7_n1_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_7_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_7_n1_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_7_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_7_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_7_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_7_n3_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_7_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_7_n3_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_7_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_8_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_8_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_8_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_8_n3_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_8_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_8_n3_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_8_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_9_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_10_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_11_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_11_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_11_n1_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_11_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_accompaniment_measure_11_n1_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_11_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_11_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_11_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_11_n3_p2",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_11_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 3
+                        },
+                        "id": "electric_accompaniment_measure_11_n3_p4",
+                        "letter": "a",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 1,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_11_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_12_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_12_n2",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_12_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_12_n3_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_12_n3_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_12_n3_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 2
+                        },
+                        "id": "electric_accompaniment_measure_12_n3_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "half"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "half"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_12_n4",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_accompaniment_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_accompaniment_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_13_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_13_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_to": "electric_accompaniment_measure_14_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_13_n1_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_to": "electric_accompaniment_measure_14_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_13_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_to": "electric_accompaniment_measure_14_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_13_n1_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "tie_to": "electric_accompaniment_measure_14_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_accompaniment_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_14_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_14_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_from": "electric_accompaniment_measure_13_n1_p1",
+                        "tie_to": "electric_accompaniment_measure_15_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_14_n1_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_from": "electric_accompaniment_measure_13_n1_p2",
+                        "tie_to": "electric_accompaniment_measure_15_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_14_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_from": "electric_accompaniment_measure_13_n1_p3",
+                        "tie_to": "electric_accompaniment_measure_15_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_14_n1_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "tie_from": "electric_accompaniment_measure_13_n1_p4",
+                        "tie_to": "electric_accompaniment_measure_15_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_accompaniment_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_accompaniment_measure_15_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_15_n1_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 4
+                        },
+                        "tie_from": "electric_accompaniment_measure_14_n1_p1",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_15_n1_p2",
+                        "letter": "b",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 4,
+                          "string": 3
+                        },
+                        "tie_from": "electric_accompaniment_measure_14_n1_p2",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_15_n1_p3",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "tie_from": "electric_accompaniment_measure_14_n1_p3",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      },
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 4
+                        },
+                        "id": "electric_accompaniment_measure_15_n1_p4",
+                        "letter": "g",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 1
+                        },
+                        "tie_from": "electric_accompaniment_measure_14_n1_p4",
+                        "written": {
+                          "dots": 0,
+                          "type": "whole"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Electric",
+        "octave_shifts": [],
+        "role": "guitar",
+        "tablature": true,
+        "tuplets": []
+      }
+    ]
+  },
+  "electric_melody": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "electric",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_electric",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_1_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_2_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_3_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_4_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_5_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_5_n1_p1",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 1,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_5_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_5_n2_p1",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 3,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_5_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_5_n3_p1",
+                        "letter": "e",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_5_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_5_n4_p1",
+                        "letter": "f",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 6,
+                          "string": 2
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_6_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_6_n1_p1",
+                        "letter": "c",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 5,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_6_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_6_n2_p1",
+                        "letter": "d",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 7,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_6_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_6_n3_p1",
+                        "letter": "e",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 9,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_6_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "electric_melody_measure_6_n4_p1",
+                        "letter": "f",
+                        "octave": 5,
+                        "tablature": {
+                          "fret": 10,
+                          "string": 3
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_7_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_9_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_10_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_melody_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_11_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_12_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_melody_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_melody_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_13_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_melody_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_14_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_melody_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_melody_measure_15_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Electric",
+        "octave_shifts": [],
+        "role": "guitar",
+        "tablature": true,
+        "tuplets": []
+      }
+    ]
+  },
+  "electric_solo": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "electric",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_electric",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_1_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_2_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_3_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_4_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_5_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_6_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_7_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_9_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_9_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_solo_measure_9_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 10,
+                          "string": 6
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_9_n3",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_9_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 5
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_solo_measure_9_n4_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 8,
+                          "string": 6
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_9_n5",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_10_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_10_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_solo_measure_10_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 10,
+                          "string": 6
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 3
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_10_n3",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 1,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 2,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_10_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 2,
+                      "numerator": 7
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 2,
+                          "numerator": 1
+                        },
+                        "id": "electric_solo_measure_10_n4_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "tablature": {
+                          "fret": 8,
+                          "string": 6
+                        },
+                        "written": {
+                          "dots": 0,
+                          "type": "eighth"
+                        }
+                      }
+                    ],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "eighth"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "electric_solo_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_11_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_12_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "electric_solo_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "electric_solo_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_13_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_solo_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_14_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "electric_solo_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "capo": 0,
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "electric_solo_measure_15_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Electric",
+        "octave_shifts": [],
+        "role": "guitar",
+        "tablature": true,
+        "tuplets": []
+      }
+    ]
+  },
+  "vocal_melody": {
+    "metadata": {
+      "composer": "",
+      "key": {
+        "alterations": [
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          },
+          {
+            "denominator": 1,
+            "numerator": 0
+          }
+        ],
+        "fifths": 0,
+        "mode": "major",
+        "tonic": {
+          "alter": {
+            "denominator": 1,
+            "numerator": 0
+          },
+          "letter": "c"
+        }
+      },
+      "key_signature": "C",
+      "tempo": 124,
+      "time_signature": "4/4",
+      "title": "Source"
+    },
+    "staves": [
+      {
+        "arranged": true,
+        "arrangement_part_type": "vocal",
+        "clef": {
+          "line": 2,
+          "octave_change": 0,
+          "sign": "G"
+        },
+        "id": "staff_arranged_vocal",
+        "instruments": [],
+        "measures": [
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_1_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_1",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "1",
+            "section_label": "Rhythm Lead-in",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_1_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_2_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_2",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "2",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_2_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_3_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_3",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "3",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_3_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_3_n1_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_3_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_3_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_3_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_3_n3_p1",
+                        "letter": "e",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_3_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_3_n4_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_4_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_4",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "4",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_4_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_4_n1_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_4_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_4_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_4_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_4_n3_p1",
+                        "letter": "e",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_4_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_4_n4_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_5_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_5",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "5",
+            "section_label": "Guitar Melody",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_5_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_6_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_6",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "6",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_6_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_7_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_7",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "7",
+            "section_label": "Acoustic Solo",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_7_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_8_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_8",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "8",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_8_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_9_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_9",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "9",
+            "section_label": "Electric Solo",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_9_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_10_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_10",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "10",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_10_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_11_h1",
+                "kind": "minor-seventh",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "d"
+                },
+                "symbol": "Dm7"
+              }
+            ],
+            "id": "vocal_melody_measure_11",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "11",
+            "section_label": "Vocal Melody",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_11_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_11_n1_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_11_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_11_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_11_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_11_n3_p1",
+                        "letter": "e",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_11_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_11_n4_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_12_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_12",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "12",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "1",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_12_n1",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_12_n1_p1",
+                        "letter": "c",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_12_n2",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_12_n2_p1",
+                        "letter": "d",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_12_n3",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 2
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_12_n3_p1",
+                        "letter": "e",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  },
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 1
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_12_n4",
+                    "kind": "note",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 3
+                    },
+                    "pitches": [
+                      {
+                        "alter": {
+                          "denominator": 1,
+                          "numerator": 0
+                        },
+                        "duration": {
+                          "denominator": 1,
+                          "numerator": 1
+                        },
+                        "id": "vocal_melody_measure_12_n4_p1",
+                        "letter": "f",
+                        "octave": 4,
+                        "written": {
+                          "dots": 0,
+                          "type": "quarter"
+                        }
+                      }
+                    ],
+                    "voice": "1",
+                    "written": {
+                      "dots": 0,
+                      "type": "quarter"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [
+              {
+                "degrees": [],
+                "id": "vocal_melody_measure_13_h1",
+                "kind": "dominant",
+                "onset": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "root": {
+                  "alter": {
+                    "denominator": 1,
+                    "numerator": 0
+                  },
+                  "letter": "g"
+                },
+                "symbol": "G7"
+              }
+            ],
+            "id": "vocal_melody_measure_13",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "13",
+            "section_label": "Ending",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_13_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "vocal_melody_measure_14",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "14",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_14_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          },
+          {
+            "attributes": [],
+            "clef": {
+              "line": 2,
+              "octave_change": 0,
+              "sign": "G"
+            },
+            "duration": {
+              "denominator": 1,
+              "numerator": 4
+            },
+            "ending_sustain": true,
+            "harmonies": [],
+            "id": "vocal_melody_measure_15",
+            "implicit": false,
+            "key": {
+              "alterations": [
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                {
+                  "denominator": 1,
+                  "numerator": 0
+                }
+              ],
+              "fifths": 0,
+              "mode": "major",
+              "tonic": {
+                "alter": {
+                  "denominator": 1,
+                  "numerator": 0
+                },
+                "letter": "c"
+              }
+            },
+            "key_signature": "C",
+            "meter": {
+              "groups": [
+                {
+                  "beats": [
+                    4
+                  ],
+                  "unit": 4
+                }
+              ]
+            },
+            "number": "15",
+            "section_label": "",
+            "staff_details": {
+              "lines": 5,
+              "tunings": []
+            },
+            "tempos": [],
+            "time_signature": "4/4",
+            "transpose": {
+              "chromatic": 0,
+              "diatonic": 0,
+              "explicit": true,
+              "octave_change": -1
+            },
+            "voices": [
+              {
+                "id": "voice_arranged",
+                "notes": [
+                  {
+                    "duration": {
+                      "denominator": 1,
+                      "numerator": 4
+                    },
+                    "hidden": false,
+                    "id": "vocal_melody_measure_15_n1",
+                    "kind": "rest",
+                    "onset": {
+                      "denominator": 1,
+                      "numerator": 0
+                    },
+                    "pitches": [],
+                    "voice": "voice_arranged",
+                    "written": {
+                      "dots": 0,
+                      "type": "whole"
+                    }
+                  }
+                ]
+              }
+            ]
+          }
+        ],
+        "name": "Vocal",
+        "octave_shifts": [],
+        "role": "vocal",
+        "tuplets": []
+      }
+    ]
+  }
+}
diff --git a/tests/production_fixtures.py b/tests/production_fixtures.py
index fd8124c..b66b766 100644
--- a/tests/production_fixtures.py
+++ b/tests/production_fixtures.py
@@ -11,7 +11,6 @@ import generator.harmonic_time
 import generator.solo.types
 import generator.solo.placement
 import generator.solo.profiles
-import generator.solo.decoder
 import generator.solo.learned
 import generator.solo.harmonic
 import dataclasses
@@ -45,6 +44,6 @@ def install(test):
   test.enterContext(unittest.mock.patch('generator.production.generate_tree', side_effect=serial))
   test.enterContext(unittest.mock.patch('generator.vocabulary.load', return_value=resources))
   test.enterContext(unittest.mock.patch('generator.solo.authored.lookup', return_value=None))
-  test.enterContext(unittest.mock.patch('generator.production._solo_model', return_value=predictor))
-  test.enterContext(unittest.mock.patch('generator.production._resource_key', return_value={'model': 'synthetic infrastructure fixture'}))
+  test.enterContext(unittest.mock.patch('generator.composition._solo_model', return_value=predictor))
+  test.enterContext(unittest.mock.patch('generator.composition._resource_key', return_value={'model': 'synthetic infrastructure fixture'}))
   test.enterContext(unittest.mock.patch('generator.solo.composer.compose', side_effect=compose))
diff --git a/tests/solo_fixtures.py b/tests/solo_fixtures.py
index 2ee41a6..2ae0b74 100644
--- a/tests/solo_fixtures.py
+++ b/tests/solo_fixtures.py
@@ -1,6 +1,6 @@
 import copy, fractions
 import generator.model, generator.parts, generator.harmony
-import generator.solo.analysis, generator.solo.composer, generator.solo.types
+import generator.source, generator.solo.composer, generator.solo.types
 import tests.test_musicxml
 import generator.harmonic_time
 
@@ -20,7 +20,7 @@ def song(meter=4, count=6, chords=('Dm7', 'G7', 'CM7')):
   return generator.parts.prepare_document(document)
 
 def compose(document, part='acoustic', cutoff=None):
-  analysis = generator.solo.analysis.analyze(document)
+  analysis = generator.source.analyze(document)
   measures = document['staves'][0]['measures']
   end = sum(generator.model.fraction(m['duration']) for m in measures) if cutoff is None else cutoff
   return generator.solo.composer.compose(analysis, measures, part, end)
diff --git a/tests/test_acoustic.py b/tests/test_acoustic.py
index 09fa7a2..9923314 100644
--- a/tests/test_acoustic.py
+++ b/tests/test_acoustic.py
@@ -1,10 +1,10 @@
+import generator.validation
 import copy
 import fractions
 import pathlib
 import unittest
 import unittest.mock
 
-import generator.accompaniment
 import generator.acoustic
 import generator.arrange.generate
 import generator.engraving.fonts
@@ -41,19 +41,19 @@ def acoustic_document(bars):
       for note in notes:
         note.update(voice=lane, stem='down' if lane == 'bass' else 'up')
       measure['voices'].append({'id': lane, 'notes': notes})
-  generator.model.validate_document(document)
+  generator.validation.validate_document(document)
   return document
 
 class AcousticTests(unittest.TestCase):
   def combine(self, document):
     generator.acoustic.prepare(document)
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     prepared = copy.deepcopy(document)
     generator.acoustic.prepare(document)
     self.assertEqual(document, prepared)
     before = sounding(document)
     generator.acoustic.combine(document)
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     self.assertEqual(sounding(document), before)
     self.assertTrue(all(len(m['voices']) == 1 for m in document['staves'][0]['measures']))
     for measure in document['staves'][0]['measures']:
@@ -130,7 +130,7 @@ class AcousticTests(unittest.TestCase):
         separate = builder(source, 'acoustic')
       combined = builder(source, 'acoustic')
       self.assertEqual(sounding(separate), sounding(combined))
-      generator.model.validate_document(combined)
+      generator.validation.validate_document(combined)
       for measure in combined['staves'][0]['measures']:
         self.assertIn(len(measure['voices']), (1, 2))
         if len(measure['voices']) == 2:
diff --git a/tests/test_acoustic_pairs.py b/tests/test_acoustic_pairs.py
index b86a39d..a85b875 100644
--- a/tests/test_acoustic_pairs.py
+++ b/tests/test_acoustic_pairs.py
@@ -1,4 +1,5 @@
 """Acoustic attack assignment across musical, rather than storage, boundaries."""
+import generator.validation
 import copy
 import dataclasses
 import fractions
@@ -108,7 +109,7 @@ class AcousticPairs(unittest.TestCase):
     source['staves'][0]['measures'] = rendered
     source['staves'][0].update(arrangement_part_type='acoustic', tablature=True)
     generator.acoustic.combine(source)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     generator.fretboard.validate_document(source)
     generator.acoustic.validate_comping(source)
     attacks = [n for n in generator.score.measure_notes(rendered[2]) if n['pitches']]
diff --git a/tests/test_acoustic_voicing.py b/tests/test_acoustic_voicing.py
index 1ab25d8..3483018 100644
--- a/tests/test_acoustic_voicing.py
+++ b/tests/test_acoustic_voicing.py
@@ -1,3 +1,4 @@
+import generator.validation
 import copy
 import fractions
 import itertools
@@ -7,11 +8,9 @@ import unittest
 import generator.accompaniment
 import generator.acoustic
 import generator.acoustic_voicing
-import generator.arrange.generate
 import generator.fretboard
 import generator.harmony
 import generator.model
-import generator.musicxml
 import tests.test_acoustic
 import tests.test_accompaniment
 
@@ -79,7 +78,7 @@ class AcousticVoicingTests(unittest.TestCase):
           self.assertIn(strings, ([5], [6]))
         self.assertFalse(any(k.startswith('_') for k in note))
         self.assertTrue(all('tie_from' not in p and 'tie_to' not in p for p in note['pitches']))
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     return spans
   def test_independent_attacks_keep_one_complete_voicing(self):
     document = planned_document([[(0, 'FM7')]])
@@ -89,7 +88,7 @@ class AcousticVoicingTests(unittest.TestCase):
     before = tests.test_acoustic.sounding(document)
     generator.acoustic.combine(document)
     self.assertEqual(tests.test_acoustic.sounding(document), before)
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
   def test_four_strings_allow_all_defined_bass_inversions(self):
     for symbol in ('CM', 'Dm', 'Caug', 'Cdim', 'C7', 'Cdim7', 'C7no5', 'C7b9', 'C7no1', 'C6', 'C13', 'Csus', 'Csus2'):
       with self.subTest(chord=symbol):
diff --git a/tests/test_arrangement_ending.py b/tests/test_arrangement_ending.py
index 23258d1..7d43bff 100644
--- a/tests/test_arrangement_ending.py
+++ b/tests/test_arrangement_ending.py
@@ -1,11 +1,14 @@
 """The held recording tail has exact score time and no vocal attacks."""
+import generator.arrange.form
+import generator.composition
+import generator.source
+import generator.validation
 import copy
 import fractions
 import pathlib
 import unittest
 
 import generator.acoustic
-import generator.arrange.ending
 import generator.arrange.generate
 import generator.fretboard
 import generator.harmony
@@ -13,7 +16,6 @@ import generator.model
 import generator.musicxml
 import generator.parts
 import generator.performance
-import generator.production
 import generator.score
 import tests.solo_fixtures
 
@@ -45,7 +47,7 @@ class ArrangementEnding(unittest.TestCase):
         self.assertEqual(generator.model.fraction(timing['sustain_start']), 672)
         self.assertEqual(generator.model.fraction(timing['duration']), 684)
         self.assertEqual(len(timing['clicks']), 672)
-        generator.model.validate_document(result)
+        generator.validation.validate_document(result)
         generator.fretboard.validate_document(result)
       self.assertEqual(source, before)
   def test_ending_uses_final_meter_and_does_not_extend_solo_windows(self):
@@ -54,10 +56,10 @@ class ArrangementEnding(unittest.TestCase):
       prepared = generator.parts.prepare_document(source)
       for part in ('acoustic', 'electric'):
         role = part + '_accompaniment'
-        result = generator.production.generate_role(generator.production.SourceAnalysis.read(prepared), role, pathlib.Path('data'))
+        result = generator.composition.generate_role(generator.source.SourceAnalysis.read(prepared), role, pathlib.Path('data'))
         tail = result['document']['staves'][0]['measures'][-3:]
         self.assertEqual([generator.model.fraction(m['duration']) for m in tail], [meter] * 3)
-        windows = generator.production.windows(prepared, part)
+        windows = generator.arrange.form.windows(prepared, part)
         self.assertEqual(windows[-1][2], role)
         self.assertEqual(windows[-1][1] - windows[-1][0], 3 * meter)
         self.assertEqual(sum(b - a for a, b, r in windows if r == part + '_solo'), 2 * meter)
diff --git a/tests/test_arrangement_pickup.py b/tests/test_arrangement_pickup.py
index 407e191..34b0868 100644
--- a/tests/test_arrangement_pickup.py
+++ b/tests/test_arrangement_pickup.py
@@ -1,9 +1,9 @@
+import generator.validation
 import copy
 import fractions
 import pathlib
 import unittest
 
-import generator.arrange.form
 import generator.arrange.generate
 import generator.arrange.pickup
 import generator.model
@@ -29,7 +29,7 @@ class ArrangementPickupTests(unittest.TestCase):
       for part in generator.parts.PART_TYPES:
         with self.subTest(song=path.stem, part=part):
           result = generator.arrange.generate.arrange_document(document, part)
-          generator.model.validate_document(result)
+          generator.validation.validate_document(result)
           measures = result['staves'][0]['measures']
           self.assertEqual(len(measures), 171)
           self.assertEqual([m['number'] for m in measures], [str(i) for i in range(1, 172)])
@@ -57,7 +57,7 @@ class ArrangementPickupTests(unittest.TestCase):
     for part, boundaries in (('vocal', (1, 5)), ('electric', (2,))):
       with self.subTest(part=part):
         result = generator.arrange.generate._arrange_document(generator.parts.prepare_document(document), part, owned={'melody', 'vocal'})
-        generator.model.validate_document(result)
+        generator.validation.validate_document(result)
         measures = result['staves'][0]['measures']
         self.assertEqual(len(measures), 9)
         for boundary in boundaries:
@@ -84,13 +84,13 @@ class ArrangementPickupTests(unittest.TestCase):
     self.assertEqual(notes[1]['lyrics'][0]['syllables'][0]['text'], 'doo')
     self.assertEqual([generator.model.fraction(n['onset']) for n in notes], [0, 1])
     document['staves'][0]['measures'] = [destination]
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
   def test_pickup_harmonies_are_planned_for_every_part_at_the_same_offset(self):
     document = source(tests.test_parts.xml_harmony('F') + tests.test_musicxml.xml_note('F', 1, 'quarter'))
     prepared = generator.parts.prepare_document(document)
     for part in generator.parts.PART_TYPES:
       result = generator.arrange.generate.arrange_document(document, part)
-      generator.model.validate_document(result)
+      generator.validation.validate_document(result)
       for index in (0, 1, 4):
         chords = result['staves'][0]['measures'][index]['harmonies']
         self.assertEqual([(generator.model.fraction(h['onset']), h['root']['letter']) for h in chords], [(0, 'c'), (3, 'f')])
@@ -102,7 +102,7 @@ class ArrangementPickupTests(unittest.TestCase):
     document = source(notes, divisions=3)
     for part in ('vocal', 'electric'):
       result = generator.arrange.generate.arrange_document(document, part)
-      generator.model.validate_document(result)
+      generator.validation.validate_document(result)
       spans = result['staves'][0]['tuplets']
       self.assertEqual(len(spans), 2 if part == 'vocal' else 1)
       self.assertEqual(len({s['id'] for s in spans}), len(spans))
diff --git a/tests/test_catalog.py b/tests/test_catalog.py
index 738e24e..8df9c68 100644
--- a/tests/test_catalog.py
+++ b/tests/test_catalog.py
@@ -1,10 +1,10 @@
+import generator.production
 import tests.production_fixtures
 import json
 import pathlib
 import tempfile
 import unittest
 
-import generator.arrange.generate
 import tests.solo_fixtures
 import tests.test_musicxml
 
@@ -16,7 +16,7 @@ class CatalogTests(unittest.TestCase):
       source, output = pathlib.Path(temporary) / 'songs', pathlib.Path(temporary) / 'output'
       source.mkdir()
       (source / 'song.xml').write_text(tests.test_musicxml.xml_score('<harmony><root><root-step>E</root-step><root-alter>-1</root-alter></root><kind>major</kind></harmony>' + tests.test_musicxml.xml_note('E', alter=-1), '<key><fifths>-3</fifths></key>'))
-      self.assertEqual(generator.arrange.generate.generate_performance_scores(source, output), 3)
+      self.assertEqual(generator.production.generate_tree(source, output), 3)
       self.assertEqual({p.name for p in output.iterdir()}, {'song_acoustic.json', 'song_electric.json', 'song_vocal.json'})
       for path in output.iterdir():
         metadata = json.loads(path.read_text())['metadata']
diff --git a/tests/test_chord_families.py b/tests/test_chord_families.py
index b640378..8ebdf1e 100644
--- a/tests/test_chord_families.py
+++ b/tests/test_chord_families.py
@@ -1,18 +1,17 @@
 """General chord families and one-voice acoustic rhythm, not song overrides."""
+import generator.composition
+import generator.validation
 import copy
 import fractions
 import unittest
 
 import generator.acoustic
-import generator.accompaniment
 import generator.chord_families
 import generator.comping
 import generator.comping_rhythm
 import generator.fretboard
-import generator.guitar
 import generator.harmony
 import generator.model
-import generator.production
 import generator.vocabulary
 import tests.solo_fixtures
 import tests.test_acoustic
@@ -89,8 +88,8 @@ class ChordFamilies(unittest.TestCase):
     changed = copy.deepcopy(resources)
     changed['accompaniment']['instruments']['acoustic']['patterns'][0]['events'][0]['duration'] = '1/2'
     for role in ('electric_accompaniment', 'electric_melody', 'electric_solo', 'vocal_melody'):
-      self.assertEqual(generator.production.dependencies(role, resources), generator.production.dependencies(role, changed))
-    self.assertNotEqual(generator.production.dependencies('acoustic_accompaniment', resources), generator.production.dependencies('acoustic_accompaniment', changed))
+      self.assertEqual(generator.composition.dependencies(role, resources), generator.composition.dependencies(role, changed))
+    self.assertNotEqual(generator.composition.dependencies('acoustic_accompaniment', resources), generator.composition.dependencies('acoustic_accompaniment', changed))
 
 class CombinedAcoustic(unittest.TestCase):
   def document(self, bars):
@@ -107,7 +106,7 @@ class CombinedAcoustic(unittest.TestCase):
   def convert(self, document):
     before = tests.test_acoustic.sounding(document)
     generator.acoustic.combine(document)
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     generator.fretboard.validate_document(document)
     self.assertEqual(tests.test_acoustic.sounding(document), before)
     self.assertTrue(all(len(m['voices']) == 1 for m in document['staves'][0]['measures']))
diff --git a/tests/test_comping_cycles.py b/tests/test_comping_cycles.py
index 64dfb26..6d5e3ea 100644
--- a/tests/test_comping_cycles.py
+++ b/tests/test_comping_cycles.py
@@ -1,4 +1,8 @@
 """Recurring source-position grooves, fills and chord-first bass behavior."""
+import generator.composition_types
+import generator.composition
+import generator.source
+import generator.validation
 import concurrent.futures
 import copy
 import dataclasses
@@ -213,7 +217,7 @@ class RecurringGrooves(unittest.TestCase):
     source['staves'][0].update(arrangement_part_type='acoustic', tablature=True)
     generator.acoustic.validate_comping(source)
     generator.acoustic.combine(source)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     generator.fretboard.validate_document(source)
     generator.acoustic.validate_comping(source)
     first = source['staves'][0]['measures'][0]
@@ -239,26 +243,26 @@ class RecurringGrooves(unittest.TestCase):
     r = generator.comping_rhythm.realize(pattern, inputs, 'acoustic', generator.comping_rhythm.melody_contexts(source))
     self.assertTrue(all(e.lane == 'combined' for e in r.events))
   def test_clean_cached_parallel_and_other_role_settings_keep_groove(self):
-    source = generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=10, chords=('C7', 'FM7')))
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=10, chords=('C7', 'FM7')))
     root = pathlib.Path('data').resolve()
     roles = ('acoustic_accompaniment', 'electric_accompaniment')
-    clean = {r: generator.production.generate_role(source, r, root) for r in roles}
+    clean = {r: generator.composition.generate_role(source, r, root) for r in roles}
     with tempfile.TemporaryDirectory() as directory:
       for r in roles:
-        cold = generator.production.generate_role(source, r, root, cache_dir=directory)
-        warm = generator.production.generate_role(source, r, root, cache_dir=directory)
+        cold = generator.composition.generate_role(source, r, root, cache_dir=directory)
+        warm = generator.composition.generate_role(source, r, root, cache_dir=directory)
         self.assertTrue(warm['cache_hit'])
         self.assertEqual(clean[r]['document'], cold['document'])
         self.assertEqual(clean[r]['document'], warm['document'])
-      generator.production.generate_role(source, roles[1], root, {'seed': 'different'}, directory)
-      self.assertEqual(clean[roles[0]]['document'], generator.production.generate_role(source, roles[0], root, cache_dir=directory)['document'])
+      generator.composition.generate_role(source, roles[1], root, {'seed': 'different'}, directory)
+      self.assertEqual(clean[roles[0]]['document'], generator.composition.generate_role(source, roles[0], root, cache_dir=directory)['document'])
     with concurrent.futures.ProcessPoolExecutor(max_workers=2, mp_context=multiprocessing.get_context('spawn')) as pool:
-      futures = {r: pool.submit(generator.production._job, (source, r, root, {}, None)) for r in reversed(roles)}
+      futures = {r: pool.submit(generator.production._job, generator.composition_types.RoleRequest(source, r, root)) for r in reversed(roles)}
       for r, future in futures.items():
         self.assertEqual(clean[r]['document'], future.result()['document'])
   def test_reuse_audit_checks_rests_and_all_six_roles(self):
     source = tests.solo_fixtures.song(count=2, chords=('C7',))
-    for role in generator.production.ROLES:
+    for role in generator.composition_types.ROLES:
       part = role.split('_')[0]
       wanted = 'slash' if role.endswith('_solo') else 'vocal' if part == 'vocal' else 'melody' if role.endswith('_melody') else 'accompaniment'
       section = generator.arrange.form.ArrangementSection('Repeated role', 0, 2, 1, wanted)
diff --git a/tests/test_comping_meters.py b/tests/test_comping_meters.py
index 94a8a21..bd3db57 100644
--- a/tests/test_comping_meters.py
+++ b/tests/test_comping_meters.py
@@ -1,4 +1,7 @@
 """Meter-specific vocabulary and source-derived quintuple grouping."""
+import generator.composition
+import generator.harmony
+import generator.source
 import concurrent.futures
 import copy
 import fractions
@@ -159,15 +162,15 @@ class CompingMeters(unittest.TestCase):
   def test_unused_meter_and_other_role_data_do_not_reseed(self):
     resources = generator.vocabulary.load()
     measures = self.source(4)['staves'][0]['measures']
-    baseline = generator.production.dependencies('acoustic_accompaniment', resources, measures)
+    baseline = generator.composition.dependencies('acoustic_accompaniment', resources, measures)
     changed = copy.deepcopy(resources)
     for role, policy in changed['accompaniment']['instruments'].items():
       for p in policy['patterns']:
         if role == 'electric' or p['meter'] in ('3/4', '5/4'):
           p['events'] = []
-    self.assertEqual(baseline, generator.production.dependencies('acoustic_accompaniment', changed, measures))
+    self.assertEqual(baseline, generator.composition.dependencies('acoustic_accompaniment', changed, measures))
     changed['accompaniment']['instruments']['acoustic']['patterns'][0]['events'] = []
-    self.assertNotEqual(baseline, generator.production.dependencies('acoustic_accompaniment', changed, measures))
+    self.assertNotEqual(baseline, generator.composition.dependencies('acoustic_accompaniment', changed, measures))
   def test_chord_changes_anticipations_and_cross_bar_ties(self):
     for beats, grouping in ((4, ()), (3, ()), (5, (3, 2)), (5, (2, 3))):
       source = self.source(beats, 2, grouping)
@@ -188,18 +191,18 @@ class CompingMeters(unittest.TestCase):
         self.assertTrue(anticipated)
   def test_roles_are_deterministic_alone_cached_and_parallel(self):
     for meter in (3, 5):
-      source = generator.production.SourceAnalysis.read(self.source(meter, 9))
+      source = generator.source.SourceAnalysis.read(self.source(meter, 9))
       roles = ('acoustic_accompaniment', 'electric_accompaniment')
       with tempfile.TemporaryDirectory() as cache:
-        clean = {r: generator.production.generate_role(source, r, pathlib.Path('data')) for r in roles}
+        clean = {r: generator.composition.generate_role(source, r, pathlib.Path('data')) for r in roles}
         for role in reversed(roles):
-          cold = generator.production.generate_role(source, role, pathlib.Path('data'), cache_dir=cache)
-          warm = generator.production.generate_role(source, role, pathlib.Path('data'), cache_dir=cache)
+          cold = generator.composition.generate_role(source, role, pathlib.Path('data'), cache_dir=cache)
+          warm = generator.composition.generate_role(source, role, pathlib.Path('data'), cache_dir=cache)
           self.assertEqual(clean[role]['document'], cold['document'])
           self.assertEqual(cold['document'], warm['document'])
           self.assertTrue(warm['cache_hit'])
         with concurrent.futures.ProcessPoolExecutor(max_workers=2, mp_context=multiprocessing.get_context('spawn')) as pool:
-          jobs = {r: pool.submit(generator.production._job, (source, r, pathlib.Path('data'), {}, None)) for r in reversed(roles)}
+          jobs = {r: pool.submit(generator.production._job, generator.composition_types.RoleRequest(source, r, pathlib.Path('data'))) for r in reversed(roles)}
           for role, job in jobs.items():
             self.assertEqual(clean[role]['document'], job.result()['document'])
 
diff --git a/tests/test_comping_rhythm.py b/tests/test_comping_rhythm.py
index 080e9f6..1defc6c 100644
--- a/tests/test_comping_rhythm.py
+++ b/tests/test_comping_rhythm.py
@@ -1,4 +1,8 @@
 """Independent rhythm contracts and their complete sounding durations."""
+import generator.composition_types
+import generator.arrange.assembly
+import generator.composition
+import generator.validation
 import copy
 import dataclasses
 import fractions
@@ -14,9 +18,8 @@ import generator.fretboard
 import generator.harmonic_time
 import generator.harmony
 import generator.model
-import generator.production
 import generator.score
-import generator.solo.analysis
+import generator.source
 import generator.solo.decoder
 import generator.solo.harmonic
 import generator.solo.learned
@@ -187,17 +190,17 @@ class LayeredComping(unittest.TestCase):
     changed = copy.deepcopy(self.source)
     changed['metadata']['tempo'] = 240
     changed['staves'][0]['measures'][0]['tempos'] = [{'onset': generator.model.rational(0), 'bpm': generator.model.rational(240), 'written': {'type': 'quarter', 'dots': 0}}]
-    a, b = map(generator.production.SourceAnalysis.read, (self.source, changed))
+    a, b = map(generator.source.SourceAnalysis.read, (self.source, changed))
     self.assertEqual(a.accompaniment_key(), b.accompaniment_key())
     for role in ('acoustic_accompaniment', 'electric_accompaniment'):
-      first = generator.production.generate_role(a, role, pathlib.Path('data'))
-      second = generator.production.generate_role(b, role, pathlib.Path('data'))
+      first = generator.composition.generate_role(a, role, pathlib.Path('data'))
+      second = generator.composition.generate_role(b, role, pathlib.Path('data'))
       self.assertEqual(sounding(first['document']), sounding(second['document']))
       self.assertEqual(first['details'], second['details'])
       self.assertNotEqual(first['trace']['cache_key'], second['trace']['cache_key'])
   def test_assembly_keeps_releases_and_canonical_reuse(self):
-    source = generator.production.SourceAnalysis.read(self.source)
-    results = {role: generator.production.generate_role(source, role, pathlib.Path('data')) for role in generator.production.ROLES if not role.endswith('_solo')}
+    source = generator.source.SourceAnalysis.read(self.source)
+    results = {role: generator.composition.generate_role(source, role, pathlib.Path('data')) for role in generator.composition_types.ROLES if not role.endswith('_solo')}
     # Silence in source-defined solo slots is sufficient to test union;
     # no generated solo participates in these accompaniment decisions.
     for part in ('acoustic', 'electric'):
@@ -207,12 +210,12 @@ class LayeredComping(unittest.TestCase):
           for n in v['notes']:
             n.update(kind='rest', pitches=[])
       results[part + '_solo'] = empty
-    assembled = generator.production.assemble(source, results)
+    assembled = generator.arrange.assembly.assemble(source, results)
     self.assertTrue(all(len(m['voices']) == 1 for m in assembled['acoustic']['staves'][0]['measures']))
     audit = generator.arrange.accompaniment.audit(self.source, assembled)
     self.assertGreater(audit['acoustic']['reused_bars'], 0)
     for doc in assembled.values():
-      generator.model.validate_document(doc)
+      generator.validation.validate_document(doc)
       generator.fretboard.validate_document(doc)
   def test_combined_voices_reject_conflicting_strings_and_fret_spans(self):
     for string, fret in ((5, 3), (2, 10)):
@@ -266,7 +269,7 @@ class SoloRhythmConditioning(unittest.TestCase):
       if held:
         m = source['staves'][0]['measures'][0]
         m['voices'][0]['notes'] = [generator.model.make_event('held', fractions.Fraction(), fractions.Fraction(4), 'note', [{'letter': 'c', 'alter': 0, 'octave': 4}])]
-      analysis = generator.solo.analysis.analyze(source)
+      analysis = generator.source.analyze(source)
       harmony = generator.solo.harmonic.Harmony(generator.harmonic_time.read(source['staves'][0]))
       examples.append({'analysis': analysis, 'harmony': harmony, 'events': [(fractions.Fraction(), fractions.Fraction(duration), 64), (fractions.Fraction(duration), fractions.Fraction(4), 67)]})
     model = generator.solo.learned.Model(generator.solo.learned.fit(examples, {'purpose': 'independently authored conditional-rhythm test'}))
diff --git a/tests/test_comping_voicings.py b/tests/test_comping_voicings.py
index 8b7c4c7..19d6bbc 100644
--- a/tests/test_comping_voicings.py
+++ b/tests/test_comping_voicings.py
@@ -1,4 +1,6 @@
 """Accompaniment geometry and whole-form movement, using authored small cases."""
+import generator.composition
+import generator.source
 import copy
 import fractions
 import itertools
@@ -14,7 +16,6 @@ import generator.fretboard
 import generator.guitar
 import generator.harmony
 import generator.model
-import generator.production
 import generator.score
 import generator.vocabulary
 import tests.solo_fixtures
@@ -43,13 +44,13 @@ class CompingVoicings(unittest.TestCase):
     path, _ = generator.comping.select_grips(((low, high),), (costs,), 'electric', 'lower', left=high, right=high)
     self.assertEqual(path, (high,))
   def test_electric_voicing_policy_does_not_reseed_rhythm(self):
-    source = generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=4, chords=('C7', 'FM7', 'Dm7', 'G7')))
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=4, chords=('C7', 'FM7', 'Dm7', 'G7')))
     root = pathlib.Path('data')
-    current = generator.production.generate_role(source, 'electric_accompaniment', root)
+    current = generator.composition.generate_role(source, 'electric_accompaniment', root)
     with tempfile.TemporaryDirectory() as cache:
       settings = {'voicing': {'register_weight': 0, 'high_position_weight': 0}}
-      other = generator.production.generate_role(source, 'electric_accompaniment', root, settings, cache)
-      warm = generator.production.generate_role(source, 'electric_accompaniment', root, settings, cache)
+      other = generator.composition.generate_role(source, 'electric_accompaniment', root, settings, cache)
+      warm = generator.composition.generate_role(source, 'electric_accompaniment', root, settings, cache)
       self.assertTrue(warm['cache_hit'])
       self.assertEqual(other['document'], warm['document'])
     self.assertNotEqual(current['trace']['cache_key'], other['trace']['cache_key'])
@@ -99,7 +100,7 @@ class CompingVoicings(unittest.TestCase):
     with generator.vocabulary.using(resources, 'acoustic_accompaniment', {'voicing': {'register_weight': -1}}), self.assertRaises(ValueError):
       generator.comping.local_cost('acoustic', key, high, 53)
   def test_production_voicing_policy_changes_cache_not_rhythm_or_electric(self):
-    source = generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=6, chords=('Em7b5', 'A7b9', 'Dm7', 'G7', 'Cm7', 'F7')))
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=6, chords=('Em7b5', 'A7b9', 'Dm7', 'G7', 'Cm7', 'F7')))
     def rhythm(result):
       return [[(n['onset'], n['duration'], n['written'], n['kind'], len(n['pitches']), tuple((bool(p.get('tie_from')), bool(p.get('tie_to'))) for p in n['pitches'])) for n in generator.score.measure_notes(m)] for m in result['document']['staves'][0]['measures']]
     with tempfile.TemporaryDirectory() as directory:
@@ -109,14 +110,14 @@ class CompingVoicings(unittest.TestCase):
       data = json.loads(role_path.read_text())
       policy = data['roles']['acoustic_accompaniment'].pop('voicing')
       role_path.write_text(json.dumps(data))
-      legacy = generator.production.generate_role(source, 'acoustic_accompaniment', root)
-      electric = generator.production.generate_role(source, 'electric_accompaniment', root)
+      legacy = generator.composition.generate_role(source, 'acoustic_accompaniment', root)
+      electric = generator.composition.generate_role(source, 'electric_accompaniment', root)
       data['roles']['acoustic_accompaniment']['voicing'] = policy
       role_path.write_text(json.dumps(data))
-      current = generator.production.generate_role(source, 'acoustic_accompaniment', root)
+      current = generator.composition.generate_role(source, 'acoustic_accompaniment', root)
       settings = {'voicing': {'register_weight': 0, 'high_position_weight': 0, 'comfortable_max_fret': 9}}
-      old = generator.production.generate_role(source, 'acoustic_accompaniment', root, settings, pathlib.Path(directory) / 'cache')
-      warm = generator.production.generate_role(source, 'acoustic_accompaniment', root, settings, pathlib.Path(directory) / 'cache')
+      old = generator.composition.generate_role(source, 'acoustic_accompaniment', root, settings, pathlib.Path(directory) / 'cache')
+      warm = generator.composition.generate_role(source, 'acoustic_accompaniment', root, settings, pathlib.Path(directory) / 'cache')
       self.assertTrue(warm['cache_hit'])
       self.assertEqual(old['document'], warm['document'])
       self.assertNotEqual(current['document'], old['document'])
@@ -125,7 +126,7 @@ class CompingVoicings(unittest.TestCase):
       self.assertEqual(legacy['document'], current['document'])
       self.assertEqual(rhythm(current), rhythm(old))
       self.assertEqual(current['details']['accompaniment_rhythm'], old['details']['accompaniment_rhythm'])
-      self.assertEqual(electric['document'], generator.production.generate_role(source, 'electric_accompaniment', root)['document'])
+      self.assertEqual(electric['document'], generator.composition.generate_role(source, 'electric_accompaniment', root)['document'])
   def test_report_balanced_cost_matches_selected_path(self):
     canonical = generator.comping.Canonical(tests.solo_fixtures.song(count=4, chords=('Em7b5', 'A7b9', 'Dm7', 'G7')), 'acoustic', 'report')
     rows = [r for r in canonical.report if r['tones']]
@@ -242,13 +243,13 @@ class CompingVoicings(unittest.TestCase):
         high = generator.comping.Canonical(source, part, 'fixed-rhythm')
       self.assertEqual(rhythm(low), rhythm(high))
   def test_accompaniment_cache_matches_clean_generation(self):
-    source = generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=3))
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=3))
     for part in ('acoustic', 'electric'):
       with tempfile.TemporaryDirectory() as directory:
         role = part + '_accompaniment'
-        cold = generator.production.generate_role(source, role, pathlib.Path('data'), cache_dir=directory)
-        warm = generator.production.generate_role(source, role, pathlib.Path('data'), cache_dir=directory)
-        clean = generator.production.generate_role(source, role, pathlib.Path('data'))
+        cold = generator.composition.generate_role(source, role, pathlib.Path('data'), cache_dir=directory)
+        warm = generator.composition.generate_role(source, role, pathlib.Path('data'), cache_dir=directory)
+        clean = generator.composition.generate_role(source, role, pathlib.Path('data'))
         self.assertTrue(warm['cache_hit'])
         self.assertEqual(cold['document'], warm['document'])
         self.assertEqual(cold['document'], clean['document'])
diff --git a/tests/test_electric_voicing.py b/tests/test_electric_voicing.py
index 6afbffd..4af4361 100644
--- a/tests/test_electric_voicing.py
+++ b/tests/test_electric_voicing.py
@@ -1,10 +1,10 @@
+import generator.validation
 import copy
 import fractions
 import pathlib
 import unittest
 import unittest.mock
 
-import generator.arrange.form
 import generator.arrange.generate
 import generator.electric
 import generator.fretboard
@@ -110,6 +110,6 @@ class ElectricVoicingTests(unittest.TestCase):
     before = copy.deepcopy(source)
     with unittest.mock.patch('generator.electric.reuse_voicings', side_effect=AssertionError('cross-part grip dependency')) as reuse:
       result = generator.arrange.generate.arrange_document(source, 'electric')
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     reuse.assert_not_called()
     self.assertEqual(source, before)
diff --git a/tests/test_engraving_cache.py b/tests/test_engraving_cache.py
index ec88c37..fadc5f8 100644
--- a/tests/test_engraving_cache.py
+++ b/tests/test_engraving_cache.py
@@ -1,3 +1,4 @@
+import generator.score_io
 import tests.production_fixtures
 import argparse
 import contextlib
@@ -19,11 +20,11 @@ import generator.engraving.cache
 import generator.engraving.fonts
 import generator.engraving.layout
 import generator.engraving.pipeline
+import generator.engraving.worker
 import generator.engraving.raster
 import generator.engraving.types
 import generator.engraving.validation
 import generator.pico_artwork
-import generator.score
 import tests.solo_fixtures
 import tests.test_musicxml
 
@@ -173,8 +174,8 @@ class EngravingCacheTests(unittest.TestCase):
     style = generator.engraving.types.Style()
     documents = [self.document, tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note('D')))]
     pages = [generator.engraving.layout.layout_score(document, style, family).pages[0] for document in documents]
-    result = generator.engraving.pipeline.GroupResult()
-    bands = generator.engraving.pipeline.BodyBands(self.root / 'spool', None, result, limit=1)
+    result = generator.engraving.worker.GroupResult()
+    bands = generator.engraving.worker.BodyBands(self.root / 'spool', None, result, limit=1)
     self.addCleanup(bands.close)
     original = None
     for index in (0, 1, 0):
@@ -338,7 +339,7 @@ class EngravingCacheTests(unittest.TestCase):
       reads.append(path)
       return read_text(path, *args, **kwargs)
     with unittest.mock.patch.object(pathlib.Path, 'read_text', read):
-      generator.score.validate_generated_tree(root)
+      generator.score_io.validate_generated_tree(root)
     self.assertCountEqual(reads, sorted(root.rglob('*.json')))
   def test_invalid_worker_count_and_overlapping_cache_are_rejected(self):
     root = self.root / 'assets'
diff --git a/tests/test_fret_policy.py b/tests/test_fret_policy.py
index cfcaed9..425301a 100644
--- a/tests/test_fret_policy.py
+++ b/tests/test_fret_policy.py
@@ -1,3 +1,5 @@
+import generator.score_io
+import generator.validation
 import copy
 import fractions
 import pathlib
@@ -14,9 +16,6 @@ import generator.fretboard
 import generator.guitar
 import generator.harmony
 import generator.model
-import generator.score
-import generator.solo.analysis
-import generator.solo.placement
 import tests.solo_fixtures
 import tests.test_acoustic_voicing
 import tests.test_musicxml
@@ -97,7 +96,7 @@ class FretPolicyTests(unittest.TestCase):
     self.assertFalse(generator.fretboard.span_penalty((position(4, 5), position(3, 6))))
     before = tests.score_events.timeline(source)
     generator.guitar.place_guitar(source)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     generator.fretboard.validate_document(source)
     self.assertEqual(tests.score_events.timeline(source), before)
     self.assertEqual([p['tablature'] for p in measure['voices'][0]['notes'][0]['pitches']], [{'string': 4, 'fret': 5}, {'string': 2, 'fret': 2}])
@@ -114,7 +113,7 @@ class FretPolicyTests(unittest.TestCase):
       states = generator.guitar.advance_positions([n], fractions.Fraction(2 * i), tones, states, True)
       self.assertEqual(min(s.cost for s in states.values()).extended_grips, 1)
     generator.guitar.place_guitar(source)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     generator.fretboard.validate_document(source)
     self.assertEqual([p['tablature'] for p in pieces[0]['pitches']], [p['tablature'] for p in pieces[1]['pitches']])
     # Removing the low anchor early still leaves an illegal high single tail.
@@ -151,7 +150,7 @@ class FretPolicyTests(unittest.TestCase):
         source = document(tuple(position(s, f) for s, f in zip((2, 1), frets)))
         if valid:
           generator.guitar.place_guitar(source)
-          generator.model.validate_document(source)
+          generator.validation.validate_document(source)
           generator.fretboard.validate_document(source)
         else:
           with self.assertRaises(ValueError):
@@ -162,7 +161,7 @@ class FretPolicyTests(unittest.TestCase):
     source = document((position(2, 12), position(1, 14)))
     anchor = tests.test_musicxml.notes(source)[0]['pitches'][0]
     anchor.update(duration=generator.model.rational(2), written=generator.model.written_for(fractions.Fraction(2)))
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     with self.assertRaisesRegex(ValueError, 'held/tied tails'):
       generator.fretboard.validate_document(source)
     with self.assertRaisesRegex(ValueError, 'no guitar placement'):
@@ -175,12 +174,12 @@ class FretPolicyTests(unittest.TestCase):
       a['tie_to'], b['tie_from'] = b['id'], a['id']
     source['staves'][0]['measures'][0]['voices'][0]['notes'] = split
     generator.guitar.place_guitar(source)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     generator.fretboard.validate_document(source)
     self.assertEqual([p['tablature'] for p in split[0]['pitches']], [p['tablature'] for p in split[1]['pitches']])
     split[0]['pitches'][0].pop('tie_to')
     split[1]['pitches'].pop(0)
-    generator.model.validate_document(source)
+    generator.validation.validate_document(source)
     with self.assertRaisesRegex(ValueError, 'held/tied tails'):
       generator.fretboard.validate_document(source)
   def test_another_voice_cannot_supply_a_single_notes_anchor(self):
@@ -221,9 +220,9 @@ class FretPolicyTests(unittest.TestCase):
     target = document(tuple(position(s, 12) for s in (3, 2, 1)))
     reference, note = tests.test_musicxml.notes(source)[0], tests.test_musicxml.notes(target)[0]
     generator.electric.reuse_voicings([generator.electric.VoicingLink(note, (reference,))])
-    generator.model.validate_document(target)
+    generator.validation.validate_document(target)
     with tempfile.TemporaryDirectory() as directory:
       output = pathlib.Path(directory) / 'score.json'
       with self.assertRaisesRegex(ValueError, 'each sounding chord requires an anchor'):
-        generator.score.write_json(output, target)
+        generator.score_io.write_json(output, target)
       self.assertFalse(output.exists())
diff --git a/tests/test_generator_boundaries.py b/tests/test_generator_boundaries.py
new file mode 100644
index 0000000..91f529e
--- /dev/null
+++ b/tests/test_generator_boundaries.py
@@ -0,0 +1,64 @@
+"""Dependency direction, cache coverage and explicit composition inputs."""
+import ast
+import json
+import pathlib
+import subprocess
+import sys
+import unittest
+import unittest.mock
+
+import generator.cache
+import generator.composition
+import generator.role_cache
+import generator.source
+import generator.vocabulary
+import tests.solo_fixtures
+
+ROOT = pathlib.Path(__file__).resolve().parents[1]
+
+class GeneratorBoundaries(unittest.TestCase):
+  def test_generator_imports_are_acyclic(self):
+    files = {'.'.join(path.relative_to(ROOT).with_suffix('').parts): path for path in (ROOT / 'generator').rglob('*.py')}
+    graph = {name: set(generator.cache.imports(path.read_bytes())) & files.keys() for name, path in files.items()}
+    visited, active = set(), []
+    def visit(name):
+      self.assertNotIn(name, active, ' -> '.join([*active, name]))
+      if name in visited:
+        return
+      active.append(name)
+      for dependency in graph[name]:
+        visit(dependency)
+      active.pop()
+      visited.add(name)
+    for name in graph:
+      visit(name)
+  def test_composition_import_does_not_load_rendering_or_publication(self):
+    code = "import generator.composition, sys, json; print(json.dumps(sorted(sys.modules)))"
+    result = subprocess.run([sys.executable, '-c', code], cwd=ROOT, capture_output=True, text=True, check=True)
+    forbidden = ('PIL', 'fontTools', 'generator.engraving', 'generator.production', 'generator.score_io')
+    self.assertFalse([name for name in json.loads(result.stdout) if name.startswith(forbidden)])
+  def test_all_previously_missing_role_dependencies_change_the_fingerprint(self):
+    baseline = generator.role_cache.code_key()
+    read = pathlib.Path.read_bytes
+    for name in ('solo/policy.py', 'source.py', 'accompaniment.py'):
+      changed = ROOT / 'generator' / name
+      with self.subTest(dependency=name):
+        def contents(path):
+          return read(path) + (b'\n# changed implementation\n' if path == changed else b'')
+        with unittest.mock.patch.object(pathlib.Path, 'read_bytes', contents):
+          self.assertNotEqual(generator.role_cache.code_key(), baseline)
+  def test_context_owns_immutable_resources_and_survives_caller_mutation(self):
+    resources = generator.vocabulary.load()
+    context = generator.vocabulary.CompositionContext.create(resources, 'electric_accompaniment')
+    expected = context.role()['center']
+    resources['roles']['roles']['electric_accompaniment']['center'] = 999
+    self.assertEqual(context.role()['center'], expected)
+    with self.assertRaises(TypeError):
+      context.data('roles')['roles']['electric_accompaniment']['center'] = 999
+    self.assertNotEqual(generator.vocabulary.load()['roles']['roles']['electric_accompaniment']['center'], 999)
+  def test_role_generation_does_not_consult_ambient_policy(self):
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=1, chords=('CM7',)))
+    with unittest.mock.patch('generator.vocabulary.current', side_effect=AssertionError('implicit policy dependency')):
+      for role in generator.composition_types.ROLES:
+        with self.subTest(role=role):
+          generator.composition.generate_role(source, role, ROOT / 'data', {'predict': True})
diff --git a/tests/test_guitar.py b/tests/test_guitar.py
index 098260c..e57b400 100644
--- a/tests/test_guitar.py
+++ b/tests/test_guitar.py
@@ -1,3 +1,5 @@
+import generator.production
+import generator.validation
 import tests.production_fixtures
 import argparse
 import copy
@@ -74,7 +76,7 @@ class GuitarTests(unittest.TestCase):
     self.assertEqual(document, before)
     document['staves'][0]['tablature'] = True
     with self.assertRaisesRegex(ValueError, 'invalid generated tablature'):
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
   def test_theory_controls_omissions_and_bass(self):
     for symbol in ('CM', 'G7b9', 'FM7#11/A', 'CmM7', 'Cdim7', 'C13', 'Csus', 'Cmadd9'):
       with self.subTest(symbol=symbol):
@@ -135,7 +137,7 @@ class GuitarTests(unittest.TestCase):
     before = copy.deepcopy(source)
     electric = tests.arrangement_fixtures.section_document(source, 'electric')
     vocal = tests.arrangement_fixtures.section_document(source, 'vocal')
-    generator.model.validate_document(electric)
+    generator.validation.validate_document(electric)
     self.assertEqual(source, before)
     self.assertEqual([(e['onset'], e['duration'], generator.model.fraction(e['pitch']) - 12) for e in tests.score_events.timeline(electric)['events']], [(e['onset'], e['duration'], generator.model.fraction(e['pitch'])) for e in tests.score_events.timeline(vocal)['events']])
     self.assertEqual([(e['pitch'], e['onset'], e['duration']) for e in tests.score_events.timeline(electric)['events']], [(e['pitch'], e['onset'], e['duration']) for e in tests.score_events.timeline(source)['events']])
@@ -156,7 +158,7 @@ class GuitarTests(unittest.TestCase):
       self.assertEqual(generator.model.pitch_number(tone), 12 * (octave + 1) + alter)
       self.assertEqual(tone['tablature'], tab)
       self.assertEqual(generator.model.fraction(tests.score_events.timeline(document)['events'][0]['pitch']), expected)
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
   def test_guitar_normalization_is_idempotent_and_respects_timed_transposition(self):
     change = '<attributes><transpose><chromatic>0</chromatic></transpose></attributes>'
     source = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note(duration=2, kind='half') + change + tests.test_musicxml.xml_note(duration=2, kind='half')))
@@ -173,7 +175,7 @@ class GuitarTests(unittest.TestCase):
       for part in generator.parts.PART_TYPES:
         with self.subTest(generator=generate.__name__, part=part):
           document = generate(source, part)
-          generator.model.validate_document(document)
+          generator.validation.validate_document(document)
           written = {p['id']: generator.model.pitch_number(p) for m in document['staves'][0]['measures'] for v in m['voices'] for n in v['notes'] for p in n['pitches']}
           events = tests.score_events.timeline(document)['events']
           self.assertTrue(events)
@@ -231,7 +233,7 @@ class GuitarTests(unittest.TestCase):
     chord['pitches'] = []
     chord['_harmony'] = generator.harmony.parse_symbol('CM')
     generator.guitar.place_guitar(document)
-    generator.model.validate_document(document)
+    generator.validation.validate_document(document)
     self.assertEqual(melody['pitches'][0]['tablature'], {'string': 1, 'fret': 12})
     self.assertNotIn(1, [p['tablature']['string'] for p in chord['pitches']])
     self.assertEqual(len(tests.score_events.timeline(document)['events']), 3)
@@ -256,9 +258,9 @@ class GuitarTests(unittest.TestCase):
       source, output = pathlib.Path(temporary) / 'source', pathlib.Path(temporary) / 'output'
       source.mkdir()
       (source / '0000.xml').write_text(tests.test_musicxml.xml_score('<harmony><root><root-step>E</root-step><root-alter>-1</root-alter></root><kind>major</kind></harmony>' + tests.test_musicxml.xml_note('E', alter=-1), '<key><fifths>-3</fifths></key>'))
-      self.assertEqual(generator.arrange.generate.generate_performance_scores(source, output), 3)
+      self.assertEqual(generator.production.generate_tree(source, output), 3)
       first = {p.name: p.read_bytes() for p in output.rglob('*.json')}
-      generator.arrange.generate.generate_performance_scores(source, output)
+      generator.production.generate_tree(source, output)
       self.assertEqual(first, {p.name: p.read_bytes() for p in output.rglob('*.json')})
   def test_unplayable_generation_preserves_previous_assets(self):
     with tempfile.TemporaryDirectory() as temporary:
diff --git a/tests/test_guitar_parts.py b/tests/test_guitar_parts.py
index 3bd6c3e..01c3b08 100644
--- a/tests/test_guitar_parts.py
+++ b/tests/test_guitar_parts.py
@@ -1,15 +1,14 @@
+import generator.score
+import generator.validation
 import copy
 import fractions
 import unittest
 
-import generator.accompaniment
 import generator.acoustic_voicing
-import generator.arrange.generate
 import generator.fretboard
 import generator.guitar
 import generator.harmony
 import generator.model
-import generator.parts
 import tests.score_events
 import tests.arrangement_fixtures
 import tests.test_accompaniment
@@ -20,7 +19,7 @@ class GuitarPartTests(unittest.TestCase):
   def section(self, content, part='electric', divisions=1):
     source = tests.test_musicxml.parse(tests.test_musicxml.xml_score(content, divisions=divisions))
     result = tests.arrangement_fixtures.section_document(source, part)
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     return result
   def test_profile_shapes_cover_defining_chord_tones(self):
     for symbol in ('CM', 'Cm', 'C7', 'CmM7', 'Csus', 'Cdim7', 'Caug7', 'C7b9', 'C13', 'CM/E'):
@@ -50,7 +49,7 @@ class GuitarPartTests(unittest.TestCase):
       self.assertTrue(all({p.midi % 12 for p in c} == {0, 7} for c in candidates))
   def test_acoustic_uses_bass_and_three_upper_notes(self):
     result = self.section(tests.test_parts.xml_harmony() + tests.test_musicxml.xml_note(), 'acoustic')
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     generator.fretboard.validate_document(result)
     sounding = [n for m in result['staves'][0]['measures'] for n in generator.score.measure_notes(m) if n['pitches']]
     self.assertTrue(sounding)
@@ -99,7 +98,7 @@ class GuitarPartTests(unittest.TestCase):
         second = tests.test_parts.xml_harmony(root) + tests.test_musicxml.xml_note('E', octave=4, extra='<tie type="stop"/>')
         source = tests.test_musicxml.parse(tests.test_accompaniment.xml_bars([first, second]))
         result = tests.arrangement_fixtures.section_document(source, 'electric')
-        generator.model.validate_document(result)
+        generator.validation.validate_document(result)
         notes = [n for m in result['staves'][0]['measures'] for v in m['voices'] for n in v['notes']]
         self.assertTrue(all(len(n['pitches']) in (3, 4) for n in notes))
         self.assertEqual(bool(notes[0]['pitches'][0].get('tie_to')), root == 'C')
diff --git a/tests/test_harmonic_recognition.py b/tests/test_harmonic_recognition.py
index 92244c4..70e638b 100644
--- a/tests/test_harmonic_recognition.py
+++ b/tests/test_harmonic_recognition.py
@@ -7,15 +7,13 @@ import unittest
 
 import generator.train
 import generator.training_io
-import generator.vocabulary
 import generator.harmonic_time
 import generator.harmony
 import generator.solo.harmonic
 import generator.solo.types
 import generator.solo.decoder
 import generator.solo.learned
-import generator.solo.analysis
-import generator.solo.expressions
+import generator.source
 import tests.solo_fixtures
 import generator.musicxml
 import generator.parts
@@ -128,7 +126,7 @@ class ContextualHarmony(unittest.TestCase):
 class PredictionReachability(unittest.TestCase):
   def engine(self, chords):
     doc = tests.solo_fixtures.song(count=2, chords=chords)
-    return generator.solo.decoder.Decoder(generator.solo.analysis.analyze(doc), generator.solo.harmonic.Harmony(tests.solo_fixtures.choices(chords)), generator.solo.learned.Model.load(ROOT / 'data/models/solo.json'), 'acoustic', fractions.Fraction(), fractions.Fraction(8))
+    return generator.solo.decoder.Decoder(generator.source.analyze(doc), generator.solo.harmonic.Harmony(tests.solo_fixtures.choices(chords)), generator.solo.learned.Model.load(ROOT / 'data/models/solo.json'), 'acoustic', fractions.Fraction(), fractions.Fraction(8))
   def test_joint_resolved_color_reaches_the_real_action_builder(self):
     d = self.engine(('C7', 'FM7'))
     n = d.note(fractions.Fraction(), fractions.Fraction(3, 2), 66)
diff --git a/tests/test_harmony.py b/tests/test_harmony.py
index f5e3dcb..ad5a235 100644
--- a/tests/test_harmony.py
+++ b/tests/test_harmony.py
@@ -6,7 +6,6 @@ import generator.engraving.fonts
 import generator.engraving.layout
 import generator.engraving.types
 import generator.harmony
-import generator.model
 import generator.musicxml
 import generator.musicxml_writer
 import generator.pitch
diff --git a/tests/test_independent_generation.py b/tests/test_independent_generation.py
index 013d2bf..9480b6f 100644
--- a/tests/test_independent_generation.py
+++ b/tests/test_independent_generation.py
@@ -1,4 +1,9 @@
 """Dependency and music contracts use synthetic sources, never audition scores."""
+import generator.composition_types
+import generator.arrange.assembly
+import generator.composition
+import generator.source
+import generator.validation
 import concurrent.futures
 import copy
 import contextlib
@@ -13,15 +18,10 @@ import unittest.mock
 
 import generator.production
 import generator.model
-import generator.vocabulary
-import generator.solo.expressions
 import generator.solo.types
 import generator.solo.harmonic
 import generator.solo.placement
 import generator.solo.notation
-import generator.solo.composer
-import tests.solo_fixtures
-import tests.solo_fixtures
 import tests.solo_fixtures
 
 def music(result):
@@ -30,23 +30,23 @@ def music(result):
 class IndependentRoles(unittest.TestCase):
   @classmethod
   def setUpClass(cls):
-    cls.source = generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=1, chords=('CM7',)))
+    cls.source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=1, chords=('CM7',)))
     cls.root = pathlib.Path('data').resolve()
   def test_alone_order_parallel_and_assembly(self):
-    serial = {role: generator.production.generate_role(self.source, role, self.root) for role in generator.production.ROLES}
+    serial = {role: generator.composition.generate_role(self.source, role, self.root) for role in generator.composition_types.ROLES}
     with concurrent.futures.ProcessPoolExecutor(max_workers=2, mp_context=multiprocessing.get_context('spawn')) as pool:
-      jobs = {role: pool.submit(generator.production._job, (self.source, role, self.root, {}, None)) for role in reversed(generator.production.ROLES)}
+      jobs = {role: pool.submit(generator.production._job, generator.composition_types.RoleRequest(self.source, role, self.root)) for role in reversed(generator.composition_types.ROLES)}
       parallel = {role: future.result() for role, future in jobs.items()}
-    for role in generator.production.ROLES:
+    for role in generator.composition_types.ROLES:
       self.assertEqual(music(serial[role]), music(parallel[role]), role)
-    for doc in generator.production.assemble(self.source, serial).values():
-      generator.model.validate_document(doc)
+    for doc in generator.arrange.assembly.assemble(self.source, serial).values():
+      generator.validation.validate_document(doc)
   def test_role_setting_and_cache_are_independent(self):
     with tempfile.TemporaryDirectory() as directory:
-      a = generator.production.generate_role(self.source, 'acoustic_solo', self.root, cache_dir=directory)
-      b = generator.production.generate_role(self.source, 'electric_solo', self.root, {'seed': 'changed'}, directory)
-      again = generator.production.generate_role(self.source, 'acoustic_solo', self.root, cache_dir=directory)
-      clean = generator.production.generate_role(self.source, 'acoustic_solo', self.root)
+      a = generator.composition.generate_role(self.source, 'acoustic_solo', self.root, cache_dir=directory)
+      b = generator.composition.generate_role(self.source, 'electric_solo', self.root, {'seed': 'changed'}, directory)
+      again = generator.composition.generate_role(self.source, 'acoustic_solo', self.root, cache_dir=directory)
+      clean = generator.composition.generate_role(self.source, 'acoustic_solo', self.root)
       self.assertTrue(again['cache_hit'])
       self.assertEqual(music(a), music(again))
       self.assertEqual(music(a), music(clean))
@@ -60,7 +60,7 @@ class IndependentRoles(unittest.TestCase):
       self.assertNotIn('generated_assets', str(path))
       return original(path, *args, **kwargs)
     with unittest.mock.patch.object(pathlib.Path, 'open', guarded):
-      result = generator.production.generate_role(self.source, 'acoustic_solo', self.root)
+      result = generator.composition.generate_role(self.source, 'acoustic_solo', self.root)
     self.assertNotIn('reference', json.dumps(result['trace']))
   def test_titles_and_export_ids_do_not_supply_musical_identity(self):
     document = tests.solo_fixtures.song(count=1, chords=('CM7',))
@@ -69,7 +69,7 @@ class IndependentRoles(unittest.TestCase):
     for m in other['staves'][0]['measures']:
       m['id'] = 'exporter_123'
       m['number'] = '99'
-    self.assertEqual(generator.production.SourceAnalysis.read(document), generator.production.SourceAnalysis.read(other))
+    self.assertEqual(generator.source.SourceAnalysis.read(document), generator.source.SourceAnalysis.read(other))
   def test_reference_presence_and_changes_do_not_change_clean_music(self):
     # No repository reference is a fixture or prerequisite. These deliberately
     # invalid optional files test the absence of a discovery/fallback branch.
@@ -78,16 +78,16 @@ class IndependentRoles(unittest.TestCase):
       reference_dir.mkdir()
       references = [reference_dir / (source_name + '-solo-' + str(index) + suffix + '.xml')
         for source_name in ('all-of-me', 'autumn-leaves') for index in (1, 2) for suffix in ('', '(4)')]
-      before = generator.production.generate_role(self.source, 'electric_solo', self.root)
+      before = generator.composition.generate_role(self.source, 'electric_solo', self.root)
       for reference in references:
         reference.write_text('<not-a-production-source/>')
-      present = generator.production.generate_role(self.source, 'electric_solo', self.root)
+      present = generator.composition.generate_role(self.source, 'electric_solo', self.root)
       for reference in references:
         reference.write_text('changed optional target, still not MusicXML')
-      changed = generator.production.generate_role(self.source, 'electric_solo', self.root)
+      changed = generator.composition.generate_role(self.source, 'electric_solo', self.root)
       for reference in references:
         reference.unlink()
-      absent = generator.production.generate_role(self.source, 'electric_solo', self.root)
+      absent = generator.composition.generate_role(self.source, 'electric_solo', self.root)
       self.assertTrue(all(music(before) == music(v) for v in (present, changed, absent)))
   def test_original_melody_changes_the_theme_with_unchanged_harmony(self):
     source = tests.solo_fixtures.song(count=4, chords=('CM7',))
@@ -97,11 +97,11 @@ class IndependentRoles(unittest.TestCase):
         for n in v['notes']:
           for p in n['pitches']:
             p['letter'] = {'c': 'e', 'd': 'f', 'e': 'g', 'f': 'a'}[p['letter']]
-    a = generator.production.generate_role(generator.production.SourceAnalysis.read(source), 'acoustic_solo', self.root)
-    b = generator.production.generate_role(generator.production.SourceAnalysis.read(changed), 'acoustic_solo', self.root)
+    a = generator.composition.generate_role(generator.source.SourceAnalysis.read(source), 'acoustic_solo', self.root)
+    b = generator.composition.generate_role(generator.source.SourceAnalysis.read(changed), 'acoustic_solo', self.root)
     self.assertNotEqual(a['details']['phrases'][0]['notes'], b['details']['phrases'][0]['notes'])
   def test_source_tuplet_lanes_survive_assembly(self):
-    serial = {r: generator.production.generate_role(self.source, r, self.root) for r in generator.production.ROLES}
+    serial = {r: generator.composition.generate_role(self.source, r, self.root) for r in generator.composition_types.ROLES}
     # Exercise a different original lane name, as in the imported Autumn head.
     doc = serial['electric_melody']['document']
     staff = doc['staves'][0]
@@ -117,10 +117,10 @@ class IndependentRoles(unittest.TestCase):
           n['voice'] = 'voice_source'
     for t in staff['tuplets']:
       t['voice'] = 'voice_source'
-    generator.model.validate_document(doc)
-    generator.model.validate_document(generator.production.assemble(self.source, serial)['electric'])
+    generator.validation.validate_document(doc)
+    generator.validation.validate_document(generator.arrange.assembly.assemble(self.source, serial)['electric'])
   def test_sparse_parts_reuse_the_canonical_form(self):
-    result = generator.production.generate_role(generator.production.SourceAnalysis.read(tests.solo_fixtures.song(count=4, chords=('Dm7', 'G7', 'CM7'))), 'acoustic_accompaniment', self.root)
+    result = generator.composition.generate_role(generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=4, chords=('Dm7', 'G7', 'CM7'))), 'acoustic_accompaniment', self.root)
     measures = result['document']['staves'][0]['measures']
     def signature(m):
       return [(n['onset'], n['duration'], [(generator.model.pitch_number(p), p['tablature']) for p in n['pitches']]) for v in m['voices'] for n in v['notes']]
diff --git a/tests/test_key_metadata.py b/tests/test_key_metadata.py
index 3ae674d..48dbf2b 100644
--- a/tests/test_key_metadata.py
+++ b/tests/test_key_metadata.py
@@ -1,3 +1,4 @@
+import generator.validation
 import copy
 import fractions
 import pathlib
@@ -43,7 +44,7 @@ class KeyCancellationTests(unittest.TestCase):
           source = key_change(old, new, local)
           before = copy.deepcopy(source)
           result = instrument_score(source, *({'A': (1, 2), 'Ab': (-1, -2), 'G': (1, 2), 'F': (-1, -2)}[target]))
-          generator.model.validate_document(result)
+          generator.validation.validate_document(result)
           measures = result['staves'][0]['measures']
           self.assertEqual(measures[0]['key'], generator.model.key_from_fifths(expected_old))
           change = measures[0]['attributes'][0] if local else measures[1]
diff --git a/tests/test_learned_solos.py b/tests/test_learned_solos.py
index fa4b596..5cd6ffa 100644
--- a/tests/test_learned_solos.py
+++ b/tests/test_learned_solos.py
@@ -1,4 +1,5 @@
 """Learned inference and explicit authored reuse have different contracts."""
+import generator.composition
 import copy
 import dataclasses
 import json
@@ -8,7 +9,6 @@ import tempfile
 import unittest
 import unittest.mock
 
-import generator.production
 import generator.parts
 import generator.musicxml
 import generator.model
@@ -21,7 +21,7 @@ import generator.solo.learned
 import generator.solo.composer
 import generator.solo.decoder
 import generator.solo.harmonic
-import generator.solo.analysis
+import generator.source
 import tests.score_events
 import tests.solo_fixtures
 import tests.test_musicxml
@@ -53,9 +53,9 @@ class TrainingAndRepertoire(unittest.TestCase):
       with self.subTest(pair=entry['id']):
         part = 'acoustic' if entry['slot'] == 1 else 'electric'
         doc = generator.parts.prepare_document(generator.musicxml.load_musicxml(ROOT / 'data/training' / entry['source']))
-        source = generator.production.SourceAnalysis.read(doc)
+        source = generator.source.SourceAnalysis.read(doc)
         with unittest.mock.patch('generator.solo.composer.compose', side_effect=AssertionError('authored pair must not be predicted')):
-          result = generator.production.generate_role(source, part + '_solo', ROOT / 'data')
+          result = generator.composition.generate_role(source, part + '_solo', ROOT / 'data')
         measures = result['document']['staves'][0]['measures']
         first = next(i for i, m in enumerate(measures) if m.get('section_label') == part.capitalize() + ' Solo')
         last = next((i for i in range(first + 1, len(measures)) if measures[i].get('section_label')), len(measures))
@@ -82,13 +82,13 @@ class TrainingAndRepertoire(unittest.TestCase):
   def test_lookup_uses_source_music_and_slot_not_title_or_path(self):
     entry = json.loads((ROOT / 'data/training/manifest.json').read_text())['examples'][0]
     doc = generator.parts.prepare_document(generator.musicxml.load_musicxml(ROOT / 'data/training' / entry['source']))
-    source = generator.production.SourceAnalysis.read(doc)
+    source = generator.source.SourceAnalysis.read(doc)
     part = 'acoustic' if entry['slot'] == 1 else 'electric'
     self.assertIsNotNone(generator.solo.authored.lookup(source, part, ROOT / 'data'))
     doc['metadata'].update(title='Renamed standard', composer='Display only')
-    self.assertEqual(source, generator.production.SourceAnalysis.read(doc))
+    self.assertEqual(source, generator.source.SourceAnalysis.read(doc))
     doc['staves'][0]['measures'][0]['voices'][0]['notes'][0]['pitches'][0]['octave'] += 1
-    self.assertIsNone(generator.solo.authored.lookup(generator.production.SourceAnalysis.read(doc), part, ROOT / 'data'))
+    self.assertIsNone(generator.solo.authored.lookup(generator.source.SourceAnalysis.read(doc), part, ROOT / 'data'))
   def test_adding_a_new_pair_requires_no_code_or_existing_song_names(self):
     with tempfile.TemporaryDirectory() as directory:
       root = pathlib.Path(directory)
@@ -102,7 +102,7 @@ class TrainingAndRepertoire(unittest.TestCase):
       examples, _ = generator.train.load_examples(manifest)
       self.assertEqual(len(examples), 1)
       doc = generator.parts.prepare_document(generator.musicxml.load_musicxml(root / 'data/songs' / source.name))
-      context = generator.production.SourceAnalysis.read(doc)
+      context = generator.source.SourceAnalysis.read(doc)
       self.assertIsNotNone(generator.solo.authored.lookup(context, 'acoustic', root / 'data'))
       self.assertIsNone(generator.solo.authored.lookup(context, 'electric', root / 'data'))
       self.assertEqual(solo.read_bytes(), (manifest.parent / solo.name).read_bytes())
@@ -130,7 +130,7 @@ class LearnedInference(unittest.TestCase):
       generator.solo.learned.Model.load('/missing-model-file')
   def test_decoder_runs_without_training_files_and_is_deterministic(self):
     source = tests.solo_fixtures.song(count=1, chords=('C7',))
-    a = generator.solo.analysis.analyze(source)
+    a = generator.source.analyze(source)
     predictor = generator.solo.learned.Model.load(ROOT / 'data/models/solo.json')
     with generator.vocabulary.using(generator.vocabulary.load(), 'acoustic_solo', {'attempts': 2}):
       original = pathlib.Path.open
@@ -146,7 +146,7 @@ class LearnedInference(unittest.TestCase):
       self.assertEqual(first.diagnostics['construction'], 'learned_joint_events')
   def test_event_score_does_not_depend_on_action_grouping(self):
     source = tests.solo_fixtures.song(count=1, chords=('C7',))
-    a = generator.solo.analysis.analyze(source)
+    a = generator.source.analyze(source)
     h = generator.solo.harmonic.Harmony(generator.harmonic_time.read(source['staves'][0]))
     predictor = generator.solo.learned.Model.load(ROOT / 'data/models/solo.json')
     engine = generator.solo.decoder.Decoder(a, h, predictor, 'acoustic', fractions.Fraction(), fractions.Fraction(4))
@@ -157,7 +157,7 @@ class LearnedInference(unittest.TestCase):
     self.assertEqual(combined, split)
   def test_source_features_include_actual_melodic_intervals(self):
     source = tests.solo_fixtures.song(count=1, chords=('C7',))
-    a = generator.solo.analysis.analyze(source)
+    a = generator.source.analyze(source)
     changed = dataclasses.replace(a, melody=tuple(dataclasses.replace(n, pitch=dataclasses.replace(n.pitch, octave=n.pitch.octave + (i == 1))) for i, n in enumerate(a.melody)))
     self.assertNotEqual(generator.solo.learned.source_feature(a, fractions.Fraction(1)), generator.solo.learned.source_feature(changed, fractions.Fraction(1)))
   def test_generated_long_nonchord_notes_still_need_support(self):
@@ -167,7 +167,7 @@ class LearnedInference(unittest.TestCase):
     self.assertTrue(h.evaluate((tests.solo_fixtures.note(0, fractions.Fraction(1, 2), 'g'), tests.solo_fixtures.note(fractions.Fraction(1, 2), 1, 'f'), tests.solo_fixtures.note(1, 2, 'e'))).valid)
   def test_held_chord_member_can_become_a_supported_color(self):
     source = tests.solo_fixtures.song(count=2, chords=('C', 'Dm'))
-    a = generator.solo.analysis.analyze(source)
+    a = generator.source.analyze(source)
     h = generator.solo.harmonic.Harmony(tests.solo_fixtures.choices(('C', 'Dm')))
     engine = generator.solo.decoder.Decoder(a, h, generator.solo.learned.Model.load(ROOT / 'data/models/solo.json'), 'acoustic', fractions.Fraction(), fractions.Fraction(8))
     n = engine.note(fractions.Fraction(3), fractions.Fraction(6), 64)  # E: C's third becomes D minor's ninth.
diff --git a/tests/test_music_model.py b/tests/test_music_model.py
index 5ca26e4..bf60d23 100644
--- a/tests/test_music_model.py
+++ b/tests/test_music_model.py
@@ -1,3 +1,4 @@
+import generator.validation
 import tests.production_fixtures
 import argparse
 import fractions
@@ -73,16 +74,16 @@ class MusicModelTests(unittest.TestCase):
     document = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
     tests.test_musicxml.notes(document)[0]['pitches'][0]['tie_to'] = 'missing'
     with self.assertRaisesRegex(ValueError, 'dangling tie'):
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
     document = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
     tests.test_musicxml.notes(document)[0]['duration'] = {'numerator': 8, 'denominator': 2}
     with self.assertRaisesRegex(ValueError, 'reduced'):
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
   def test_optional_turnaround_and_form(self):
     source = generator.musicxml.load_musicxml(pathlib.Path('data/songs/all-of-me.xml'))
     for part in ('acoustic', 'electric', 'vocal'):
       result = generator.arrange.generate.arrange_document(source, part)
-      generator.model.validate_document(result)
+      generator.validation.validate_document(result)
       measures = result['staves'][0]['measures']
       self.assertEqual([m['section_label'] for m in measures if m.get('section_label')], ['Rhythm Lead-in', 'Vocal Melody', 'Guitar Melody', 'Acoustic Solo', 'Electric Solo', 'Vocal Melody', 'Ending'])
       self.assertFalse(measures[-1]['harmonies'])
@@ -96,12 +97,12 @@ class MusicModelTests(unittest.TestCase):
       source = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
       source['staves'][0]['measures'][0][field] = {}
       with self.assertRaisesRegex(ValueError, 'repeat notation'):
-        generator.model.validate_document(source)
+        generator.validation.validate_document(source)
     for field in ('sound_ties', 'printed_ties'):
       source = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
       tests.test_musicxml.notes(source)[0]['pitches'][0][field] = []
       with self.assertRaisesRegex(ValueError, 'pass-specific tie'):
-        generator.model.validate_document(source)
+        generator.validation.validate_document(source)
   def test_failure_preserves_generated_assets(self):
     with tempfile.TemporaryDirectory() as temp:
       root = pathlib.Path(temp)
@@ -149,7 +150,7 @@ class MusicModelTests(unittest.TestCase):
     source = tests.test_musicxml.xml_score(tests.test_musicxml.xml_note(duration=1, kind='quarter', extra='<tie type="start"/>'), implicit=True)
     source = source.replace('</measure></part>', '</measure><measure number="2">' + tests.test_musicxml.xml_note(extra='<tie type="stop"/>') + '</measure></part>')
     result = generator.arrange.generate.arrange_document(tests.test_musicxml.parse(source), 'vocal')
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     measures = result['staves'][0]['measures']
     start = measures[0]['voices'][0]['notes'][-1]['pitches'][0]
     end = measures[1]['voices'][0]['notes'][0]['pitches'][0]
diff --git a/tests/test_output_contract.py b/tests/test_output_contract.py
new file mode 100644
index 0000000..117a6ff
--- /dev/null
+++ b/tests/test_output_contract.py
@@ -0,0 +1,20 @@
+"""Exact role scores protect musical choices, notation, IDs and tablature."""
+import generator.composition_types
+import generator.composition
+import generator.source
+import json
+import pathlib
+import unittest
+
+import tests.solo_fixtures
+
+class OutputContract(unittest.TestCase):
+  def test_complete_roles_including_learned_fallback_match_reviewed_output(self):
+    root = pathlib.Path(__file__).resolve().parents[1]
+    expected = json.loads((root / 'tests/fixtures/role_outputs.json').read_text())
+    source = generator.source.SourceAnalysis.read(tests.solo_fixtures.song(count=2, chords=('Dm7', 'G7')))
+    for role in generator.composition_types.ROLES:
+      with self.subTest(role=role):
+        settings = {'predict': True} if role.endswith('_solo') else {}
+        actual = generator.composition.generate_role(source, role, root / 'data', settings)['document']
+        self.assertEqual(actual, expected[role])
diff --git a/tests/test_parts.py b/tests/test_parts.py
index 37e5de4..c61e143 100644
--- a/tests/test_parts.py
+++ b/tests/test_parts.py
@@ -1,3 +1,6 @@
+import generator.production
+import generator.score
+import generator.validation
 import tests.production_fixtures
 import argparse
 import copy
@@ -10,11 +13,9 @@ import unittest.mock
 import xml.etree.ElementTree
 
 import generator.__main__
-import generator.accompaniment
 import generator.arrange.generate
 import generator.model
 import generator.musicxml
-import generator.parts
 import generator.pitch
 import tests.score_events
 import tests.arrangement_fixtures
@@ -37,7 +38,7 @@ class PartGenerationTests(unittest.TestCase):
   def test_dense_melody_keeps_rhythmic_accompaniment_without_sustaining_across_changes(self):
     source = tests.test_musicxml.parse(tests.test_musicxml.xml_score(xml_harmony() + xml_harmony('F', offset=3) + ''.join(tests.test_musicxml.xml_note(duration=1, kind='eighth') for _ in range(8)), divisions=2))
     for result in (tests.arrangement_fixtures.section_document(source, 'acoustic'), generator.arrange.generate.arrange_document(source, 'electric')):
-      generator.model.validate_document(result)
+      generator.validation.validate_document(result)
       for measure in result['staves'][0]['measures']:
         events = measure['voices'][0]['notes']
         if measure.get('ending_sustain'):
@@ -72,13 +73,13 @@ class PartGenerationTests(unittest.TestCase):
     self.assertTrue(all(generator.model.pitch_number(p) % 12 in {0, 5, 9} for n in carried for p in n['pitches']))
     for index in (2, 3):
       self.assertTrue(all(n['kind'] == 'rest' and not n['pitches'] for n in tests.test_musicxml.notes(result, index)))
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
   def test_sparse_accompaniment_preserves_form_and_intentional_space(self):
     bar = xml_harmony() + ''.join(tests.test_musicxml.xml_note(duration=1, kind='quarter') for _ in range(4))
     xml = tests.test_musicxml.xml_score(bar).replace('</part>', ''.join(f'<measure number="{i}">{bar}</measure>' for i in range(2, 13)) + '</part>')
     result = tests.arrangement_fixtures.section_document(tests.test_musicxml.parse(xml), 'acoustic')
     self.assertEqual(len(result['staves'][0]['measures']), 12)
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     self.assertTrue(tests.score_events.timeline(result)['events'])
     self.assertTrue(any(n['kind'] == 'rest' for m in result['staves'][0]['measures'] for n in generator.score.measure_notes(m)))
   def test_melody_written_pitch_rhythm_rests_and_cross_bar_ties_are_preserved(self):
@@ -97,7 +98,7 @@ class PartGenerationTests(unittest.TestCase):
       for part in ('electric', 'vocal'):
         with self.subTest(builder=builder.__module__, part=part):
           result = builder(source, part)
-          generator.model.validate_document(result)
+          generator.validation.validate_document(result)
           measures = result['staves'][0]['measures']
           starts = [0] if builder is tests.arrangement_fixtures.section_document else [i for i, m in enumerate(measures) if m.get('section_label') == ('Guitar Melody' if part == 'electric' else 'Vocal Melody')]
           self.assertTrue(starts)
@@ -131,7 +132,7 @@ class PartGenerationTests(unittest.TestCase):
         for name in names:
           (source / (name + '.xml')).write_text(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
         with self.assertRaisesRegex(ValueError, 'conflicting output path') as raised:
-          generator.arrange.generate.generate_performance_scores(source, output)
+          generator.production.generate_tree(source, output)
         for name in names:
           self.assertIn(str(source / (name + '.xml')), str(raised.exception))
         self.assertEqual([p.name for p in output.iterdir()], ['sentinel'])
@@ -148,7 +149,7 @@ class PartGenerationTests(unittest.TestCase):
         unittest.mock.patch('generator.engraving.pipeline.engrave_tree'),
         unittest.mock.patch('generator.pico_artwork.generate_titles'),
         unittest.mock.patch('generator.catalog.build_catalog'),
-        unittest.mock.patch('generator.performance.copy_audio', return_value=[]),
+        unittest.mock.patch('generator.audio_assets.copy_audio', return_value=[]),
       ):
         generator.__main__.generate_assets(args)
       # Role catalog loading is replaced by this infrastructure fixture. The
diff --git a/tests/test_performance.py b/tests/test_performance.py
index e2d97f3..8757022 100644
--- a/tests/test_performance.py
+++ b/tests/test_performance.py
@@ -1,3 +1,4 @@
+import generator.audio_assets
 import argparse
 import copy
 import hashlib
@@ -41,7 +42,7 @@ def fixture(root):
     with wave.open(str(path), 'wb') as output:
       output.setparams((2, 2, 48000, 0, 'NONE', ''))
       output.writeframes(value.to_bytes(2, 'little', signed=True) * 2 * frames)
-    entries.append(generator.performance.describe_wav(path, root, song_id=song_id, bpm=bpm))
+    entries.append(generator.audio_assets.describe_wav(path, root, song_id=song_id, bpm=bpm))
   (root / 'manifest.audio').write_text(json.dumps(entries))
 
 class PerformanceTests(unittest.TestCase):
@@ -49,7 +50,7 @@ class PerformanceTests(unittest.TestCase):
     source = pathlib.Path('package/assets')
     with tempfile.TemporaryDirectory() as temporary:
       root = pathlib.Path(temporary)
-      entries = generator.performance.copy_audio(source, root, {'all_of_me', 'autumn_leaves'})
+      entries = generator.audio_assets.copy_audio(source, root, {'all_of_me', 'autumn_leaves'})
       self.assertEqual(len(entries), 4)
       for entry in entries:
         self.assertEqual((source / entry['path']).read_bytes(), (root / entry['path']).read_bytes())
@@ -61,10 +62,10 @@ class PerformanceTests(unittest.TestCase):
       path = root / 'backing/fixture_120.wav'
       path.write_bytes(path.read_bytes()[:-2])
       with self.assertRaisesRegex(ValueError, 'truncated'):
-        generator.performance.describe_wav(path, root)
+        generator.audio_assets.describe_wav(path, root)
       path.rename(root / 'backing/fixture_115.wav')
       with self.assertRaisesRegex(ValueError, 'unsupported'):
-        generator.performance.copy_audio(root, root / 'out', {'fixture'})
+        generator.audio_assets.copy_audio(root, root / 'out', {'fixture'})
   def test_short_backing_cannot_publish(self):
     with tempfile.TemporaryDirectory() as temporary:
       root = pathlib.Path(temporary)
@@ -73,10 +74,10 @@ class PerformanceTests(unittest.TestCase):
       bundle = json.loads((root / 'score.json').read_text())
       (root / 'songs/fixture.json').write_text(json.dumps(bundle['music']))
       entries = json.loads((root / 'manifest.audio').read_text())
-      generator.performance.validate_recording_lengths(root, entries)
+      generator.audio_assets.validate_recording_lengths(root, entries)
       entries[-1]['frames'] = 1
       with self.assertRaisesRegex(ValueError, 'shorter'):
-        generator.performance.validate_recording_lengths(root, entries)
+        generator.audio_assets.validate_recording_lengths(root, entries)
   def test_page_coverage_and_measure_accents(self):
     with tempfile.TemporaryDirectory() as temporary:
       root = pathlib.Path(temporary)
diff --git a/tests/test_printing.py b/tests/test_printing.py
index 86a41a4..4ac4b17 100644
--- a/tests/test_printing.py
+++ b/tests/test_printing.py
@@ -1,4 +1,5 @@
 """Build-only print layout, PDF contents and reproducible cache behavior."""
+import generator.score_io
 import copy
 import dataclasses
 import io
@@ -14,11 +15,9 @@ import PIL.PdfParser
 import generator.arrange.generate
 import generator.engraving.audit
 import generator.engraving.fonts
-import generator.engraving.types
 import generator.model
 import generator.musicxml
 import generator.printing
-import generator.score
 import tests.solo_fixtures
 import tests.test_musicxml
 
@@ -35,7 +34,7 @@ class PrintableParts(unittest.TestCase):
   def tree(self, name, document=None):
     root = self.root / name
     (root / 'songs').mkdir(parents=True)
-    generator.score.write_json(root / 'songs/part.json', document or self.source)
+    generator.score_io.write_json(root / 'songs/part.json', document or self.source)
     return root
   def test_letter_pagination_preserves_complete_order_without_transition_duplicates(self):
     source = tests.solo_fixtures.song(count=32, chords=('C7',))
@@ -137,7 +136,7 @@ class PrintableParts(unittest.TestCase):
     generator.printing.generate_tree(root, self.font_path, cache_dir=cache)
     changed = copy.deepcopy(self.source)
     changed['metadata']['title'] = 'Another title'
-    generator.score.write_json(root / 'songs/part.json', changed)
+    generator.score_io.write_json(root / 'songs/part.json', changed)
     with unittest.mock.patch('generator.printing.write_pdf', wraps=generator.printing.write_pdf) as render:
       generator.printing.generate_tree(root, self.font_path, cache_dir=cache)
     render.assert_called_once()
diff --git a/tests/test_publish_package.py b/tests/test_publish_package.py
index d01f8b2..39db59b 100644
--- a/tests/test_publish_package.py
+++ b/tests/test_publish_package.py
@@ -4,7 +4,9 @@ import unittest
 import unittest.mock
 
 import modulus.artifacts
-import modulus.cli
+import modulus.build_context
+import modulus.packaging
+import modulus.process
 import modulus.config
 import modulus.python
 
@@ -13,17 +15,17 @@ class PackagePublishingTests(unittest.TestCase):
     root = pathlib.Path(__file__).resolve().parents[1]
     with tempfile.TemporaryDirectory() as temporary:
       directory = pathlib.Path(temporary)
-      context = modulus.cli.build_context(directory, modulus.config.load_repo_config(root))
+      context = modulus.build_context.build_context(directory, modulus.config.load_repo_config(root))
       def fake_build(context, command, **kwargs):
         if command[:2] == ['cmake', '--install']:
           stage = pathlib.Path(command[2]).parent / 'stage'
           (stage / 'manifest.json').write_text('{}\n')
         return 0
-      with unittest.mock.patch.object(modulus.cli, 'in_docker', return_value=True), \
-        unittest.mock.patch.object(modulus.cli, 'run', side_effect=fake_build), \
+      with unittest.mock.patch.object(modulus.process, 'in_docker', return_value=True), \
+        unittest.mock.patch.object(modulus.process, 'run', side_effect=fake_build), \
         unittest.mock.patch.object(modulus.python, 'interpreter', return_value=pathlib.Path('/usr/bin/python3')), \
         unittest.mock.patch.object(modulus.artifacts, 'main') as publish:
-        self.assertEqual(modulus.cli.package_artifacts(context, ['--no-remote']), 0)
+        self.assertEqual(modulus.packaging.package_artifacts(context, ['--no-remote']), 0)
         publish.assert_not_called()
       artifacts = modulus.artifacts.discover_artifacts(directory / 'build/packages', context.package['name'], context.artifact['targets'])
       self.assertEqual([p.name for p in artifacts], ['product_vamp_arm_64_gcc12_release.tar.gz', 'product_vamp_arm_64_gcc12_release.tar.gz.sha256'])
diff --git a/tests/test_score_bundle.py b/tests/test_score_bundle.py
index 476af05..5d4514b 100644
--- a/tests/test_score_bundle.py
+++ b/tests/test_score_bundle.py
@@ -1,3 +1,5 @@
+import generator.score_io
+import generator.validation
 import tests.production_fixtures
 import argparse
 import copy
@@ -14,7 +16,6 @@ import xml.etree.ElementTree
 import PIL.Image
 import PIL.ImageChops
 
-import generator.__main__
 import generator.arrange.generate
 import generator.engraving.fonts
 import generator.engraving.layout
@@ -30,7 +31,6 @@ import generator.performance
 import generator.pitch
 import tests.score_events
 import tests.arrangement_fixtures
-import generator.score
 import generator.theme
 import tests.musicxml_roundtrip
 import tests.test_musicxml
@@ -48,7 +48,7 @@ class ScoreBundleTests(unittest.TestCase):
     self.assertEqual(set(document), {'metadata', 'staves'})
     for malformed in (None, [], {}, {'metadata': {}, 'staves': []}, {**document, 'staves': None}, {**document, 'staves': [{}]}):
       with self.subTest(document=malformed), self.assertRaises(ValueError):
-        generator.model.validate_document(malformed)
+        generator.validation.validate_document(malformed)
   def test_multiple_voices_keep_independent_ties_and_transformations(self):
     def half(action):
       return tests.test_musicxml.xml_note(duration=2, kind='half', extra=f'<voice>1</voice><tie type="{action}"/>')
@@ -59,9 +59,9 @@ class ScoreBundleTests(unittest.TestCase):
     self.assertEqual([v['id'] for v in measure['voices']], ['1', '2'])
     self.assertNotIn('tie_from', measure['voices'][1]['notes'][0]['pitches'][0])
     for document in (source, generator.pitch.concert_document(source), generator.arrange.generate.arrange_document(source, 'vocal')):
-      generator.model.validate_document(document)
+      generator.validation.validate_document(document)
       restored = self.round_trip(document)
-      generator.model.validate_document(restored)
+      generator.validation.validate_document(restored)
       self.assertTrue(any(len(m['voices']) == 2 for m in restored['staves'][0]['measures']))
   def test_contiguous_ties_continue_across_systems_without_repeat_state(self):
     text = tests.test_musicxml.xml_score(tests.test_musicxml.xml_note(extra='<tie type="start"/>'))
@@ -139,7 +139,7 @@ class ScoreBundleTests(unittest.TestCase):
         tests.musicxml_roundtrip.audit_roundtrip(before, after)
     source['staves'][0]['instruments'] = []
     with self.assertRaisesRegex(ValueError, 'unknown score instrument'):
-      generator.model.validate_document(source)
+      generator.validation.validate_document(source)
   def test_catalog_roundtrip_preserves_written_pitch_and_rhythm(self):
     for path in sorted(pathlib.Path('data/songs').glob('*.xml')):
       with self.subTest(path=path):
@@ -220,34 +220,34 @@ class ScoreBundleTests(unittest.TestCase):
       bundle['performance'] = generator.performance.timing(document)
       path = assets / 'score.json'
       path.write_text(json.dumps(bundle))
-      self.assertEqual(generator.score.load_json(path), document)
+      self.assertEqual(generator.score_io.load_json(path), document)
       page.write_bytes(data + b'corrupt')
       with self.assertRaisesRegex(ValueError, 'checksum'):
-        generator.score.load_json(path)
+        generator.score_io.load_json(path)
       page.unlink()
       outside = root / 'outside.png'
       outside.write_bytes(data)
       page.symlink_to(outside)
       with self.assertRaisesRegex(ValueError, 'escapes'):
-        generator.score.load_json(path)
+        generator.score_io.load_json(path)
   def test_final_validation_reuses_content_checks_and_rechecks_files(self):
     with tempfile.TemporaryDirectory() as temporary:
       root = pathlib.Path(temporary)
       document = tests.test_musicxml.parse(tests.test_musicxml.xml_score(tests.test_musicxml.xml_note()))
       for index in range(3):
-        generator.score.write_json(root / 'songs' / f'{index}.json', document)
+        generator.score_io.write_json(root / 'songs' / f'{index}.json', document)
       trusted = generator.engraving.pipeline.engrave_tree(root, pathlib.Path('package/assets/fonts/petaluma'))
       generator.pico_artwork.generate_titles(root, pathlib.Path('package/assets/fonts/petaluma'))
       with unittest.mock.patch('generator.engraving.validation.check_content', side_effect=AssertionError('already validated content')):
-        generator.score.validate_generated_tree(root, trusted)
+        generator.score_io.validate_generated_tree(root, trusted)
         page = root / 'songs/2.pages/0001.png'
         original = page.read_bytes()
         page.write_bytes(original + b'changed')
         with self.assertRaisesRegex(ValueError, 'checksum'):
-          generator.score.validate_generated_tree(root, trusted)
+          generator.score_io.validate_generated_tree(root, trusted)
         page.write_bytes(original)
       with unittest.mock.patch('generator.engraving.validation.check_content', wraps=generator.engraving.validation.check_content) as decode:
-        generator.score.validate_generated_tree(root)
+        generator.score_io.validate_generated_tree(root)
       decode.assert_called_once()
       PIL.Image.new('RGB', (976, 484), generator.theme.rgb('background')).save(page)
       path = root / 'songs/2.json'
@@ -255,14 +255,14 @@ class ScoreBundleTests(unittest.TestCase):
       bundle['presentation']['pages'][0]['sha256'] = hashlib.sha256(page.read_bytes()).hexdigest()
       path.write_text(json.dumps(bundle))
       with self.assertRaisesRegex(ValueError, 'blank page'):
-        generator.score.validate_generated_tree(root, trusted)
+        generator.score_io.validate_generated_tree(root, trusted)
   def test_python_engraver_visual_golden_and_determinism(self):
     document = generator.musicxml.load_musicxml(pathlib.Path('tests/fixtures/engraving.xml'))
     with tempfile.TemporaryDirectory() as temporary:
       root = pathlib.Path(temporary)
       before = None
       for _ in range(2):
-        generator.score.write_json(root / 'fixture.json', document)
+        generator.score_io.write_json(root / 'fixture.json', document)
         generator.engraving.pipeline.engrave_tree(root, pathlib.Path('package/assets/fonts/petaluma'))
         bundle = json.loads((root / 'fixture.json').read_text())
         self.assertEqual(bundle['music'], document)
diff --git a/tests/test_score_loader.cpp b/tests/test_score_loader.cpp
index 545253e..f9d52e1 100644
--- a/tests/test_score_loader.cpp
+++ b/tests/test_score_loader.cpp
@@ -14,6 +14,7 @@
 #include <boost/asio/redirect_error.hpp>
 #include <boost/asio/steady_timer.hpp>
 #include <boost/asio/use_awaitable.hpp>
+#include <boost/asio/thread_pool.hpp>
 
 #include <vamp_zero/errors.hpp>
 #include <vamp_zero/score_loader.hpp>
@@ -93,6 +94,38 @@ BOOST_AUTO_TEST_CASE(score_loader_starts_asynchronously_from_executor_handler) {
   BOOST_CHECK_EQUAL(*fixture.completions, 1U);
 }
 
+BOOST_AUTO_TEST_CASE(score_loader_worker_keeps_control_executor_responsive_and_returns_completion) {
+  auto io = boost::asio::io_context{};
+  auto worker = boost::asio::thread_pool{1};
+  auto entered = std::promise<void>{};
+  auto release = std::promise<void>{};
+  auto resume = release.get_future().share();
+  auto completed = false;
+  auto control_thread = std::this_thread::get_id();
+  auto loader = vamp_zero::score_loader{io.get_executor(),
+                                        [&entered, resume](vamp_zero::score_reference reference) -> boost::asio::awaitable<std::expected<vamp_zero::score_document, modulus::error>> {
+                                          entered.set_value();
+                                          resume.wait();
+                                          co_return vamp_zero::score_document{.id = reference.id};
+                                        },
+                                        [&] { completed = true; BOOST_CHECK(std::this_thread::get_id() == control_thread); }, worker.get_executor()};
+  loader.select(std::make_shared<vamp_zero::catalog>(), performance("a"));
+  auto started = entered.get_future().wait_for(std::chrono::seconds{2}) == std::future_status::ready;
+  auto serviced = false;
+  boost::asio::post(io, [&] { serviced = true; });
+  io.poll();
+  BOOST_CHECK(serviced);
+  BOOST_CHECK(!completed);
+  release.set_value();
+  worker.join();
+  io.restart();
+  io.run();
+  BOOST_REQUIRE(started);
+  BOOST_CHECK(completed);
+  BOOST_REQUIRE(loader.snapshot().document);
+  BOOST_CHECK_EQUAL(loader.snapshot().document->id, "a");
+}
+
 BOOST_AUTO_TEST_CASE(score_loader_coalesces_pending_and_discards_stale_results) {
   auto fixture = loader_fixture{};
   fixture.loader.select(fixture.catalog, performance("a"));
diff --git a/tests/test_six_parts.py b/tests/test_six_parts.py
index 28f5323..8e1ce70 100644
--- a/tests/test_six_parts.py
+++ b/tests/test_six_parts.py
@@ -3,18 +3,11 @@ import dataclasses
 import fractions
 import unittest
 
-import generator.arrange.generate
-import generator.arrange.form
 import generator.model
 import generator.parts
-import generator.solo.arrangement
-import generator.solo.analysis
+import generator.source
 import generator.solo.profiles
 import generator.solo.placement
-import generator.solo.types
-import generator.solo.harmonic
-import tests.solo_fixtures
-import tests.solo_fixtures
 import tests.solo_fixtures
 
 def events(measure):
@@ -39,7 +32,7 @@ class SoloInstrumentAndIdentity(unittest.TestCase):
     self.assertTrue(any(p.string_number == 1 for p in generator.solo.placement.positions(65, electric)))
     self.assertTrue(any(p.string_number == 1 for p in generator.solo.placement.positions(65, acoustic)))
   def test_soft_overlapping_registers_do_not_inherit_a_mandatory_octave(self):
-    source = generator.solo.analysis.analyze(generator.parts.prepare_document(tests.solo_fixtures.song(count=4, chords=('CM7',))))
+    source = generator.source.analyze(generator.parts.prepare_document(tests.solo_fixtures.song(count=4, chords=('CM7',))))
     acoustic = generator.solo.profiles.for_part('acoustic', source)
     electric = generator.solo.profiles.for_part('electric', source)
     self.assertIsNone(electric.reference)
diff --git a/tests/test_voicing.py b/tests/test_voicing.py
index 0daeae8..06f600c 100644
--- a/tests/test_voicing.py
+++ b/tests/test_voicing.py
@@ -1,3 +1,4 @@
+import generator.validation
 import copy
 import pathlib
 import unittest
@@ -209,7 +210,7 @@ class VoicingTests(unittest.TestCase):
     source = generator.musicxml.load_musicxml(pathlib.Path('data/songs/autumn_leaves.xml'))
     before = copy.deepcopy(source)
     result = generator.arrange.generate.arrange_document(source, 'electric')
-    generator.model.validate_document(result)
+    generator.validation.validate_document(result)
     section, checked = '', set()
     source_index = generator.score.body_start_measure_index(source['staves'][0]['measures'])
     for measure in result['staves'][0]['measures']: