Rhythm Patterns

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khodowany
2026-10-06 23:55:58 -05:00
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@@ -102,11 +102,13 @@ Six roles generate independently: acoustic accompaniment/solo; electric accompan
Electric accompaniment and electric melody share compact chord families on strings 1–4. Melody harmonization adapts these to keep the original melody on the lowest-numbered feasible string, preferring it above the added chord tones. The separate Electric Solo stays monophonic. Acoustic accompaniment uses one bass note on string 5 or 6 and three upper notes on strings 2, 3 and 4. Transposable degree families cover triads, sevenths/sixths, suspensions, diminished/augmented and extended/altered chords, with root/fifth bass alternatives on both bass strings. Plain major/minor chords also allow third basses; explicit slash basses and inversions take priority. Unplayable variants are discarded. Each instrument selects a connected voicing path across the source form to reduce hand movement, then reuses it through the arrangement.
Accompaniment uses independently authored two-bar jazz pattern families: Charleston and shifted Charleston, forward-motion syncopation, anticipated heavy beats, syncopated riffs, quarters, dotted spacing, shifting motifs, call-response and anticipated beat four. Acoustic distributes a single figure between bass and upper chord, normally 1–3 total attacks per full bar, without mandatory beat-one bass. Separate attacks are quarters/eighths and never overlap; a combined bass-plus-upper chord is allowed only when both attack and sustain together for more than one beat. Electric has distinct patterns with normally 0–2 attacks per bar, stabs, sustained chords and space. The source melody and harmonic rhythm guide complete-pattern selection. Half-beat upper/electric anticipations may establish the next written chord; bass stays on current harmony. Explicit cross-bar holds use ties, never automatic merging of repeated attacks. Canonical patterns repeat at corresponding form positions with documented harmonic/pickup exceptions, and changing only tempo leaves the music unchanged.
Accompaniment uses independently authored two-bar jazz pattern families, chosen against each song's original melody and harmonic rhythm. Acoustic repeats two patterns (A–B); electric repeats four (A–B–C–D). Occasional source-phrase-ending fills recur at the same positions in every iteration; both instruments allow at most one per eight full measures, including the repeat join. Acoustic normally has 1–3 attack positions per full bar with quarter/eighth bass and upper-chord notes that may overlap or sound together. Electric has distinct patterns with normally 0–2 attacks per bar, stabs, sustains and space. Cross-bar holds use ties; repeated attacks remain attacks. Pattern phase follows source-form position, including partial entries and odd-length forms. Meter changes use compatible cycles, with explicit diagnostics if fewer distinct patterns are available. Tempo changes do not reshuffle the accompaniment.
Both accompaniment parts balance movement with sounding register and a soft cost for mean fret positions above nine; comfortable shifts can win over staying high. Acoustic uses a register center of MIDI 53 and electric uses 60. Compact spans and preferred chord families remain higher priorities, including for the final sustained chord. Electric melody's supporting chords use the same balance after the existing melody-string and foreground priorities; the original melody pitches and rhythm remain fixed. Voicing preferences do not reseed accompaniment rhythms.
The first new acoustic accompaniment attack in every measure includes bass, either alone or with the upper chord in a combined sustain longer than one beat. This can be a delayed entrance; no beat-one attack is required. Pattern fitting exchanges upper/bass assignments when needed, without inserting attacks. Tied carries and silent bars do not require a new bass attack.
The first acoustic attack for each new chord includes bass, alone or paired with the upper chord. A mid-measure change follows this rule; an unchanged chord crossing a barline does not create a bass obligation. Delayed entrances remain delayed. A qualified half-beat anticipated chord includes its bass at the anticipated entrance. Bass and upper notes share one engraved part, with ties preserving overlaps and independent releases.
Each song has six canonical roles: electric melody, electric accompaniment, electric solo, acoustic accompaniment, acoustic solo, and vocal melody. Matching source-form positions reuse the same musical events and TAB whenever a role returns. Final-turnaround omission changes only affected harmony; source-defined pickups/handoffs and the three-bar instrumental closing sustain remain explicit exceptions.
**Registered Solo 1 is notated exactly in the acoustic part and Solo 2 exactly in the electric part.** Unregistered song/slot pairs use deterministic prediction from one pooled statistical model trained on both slots. There is no learned acoustic/electric style distinction. Prediction uses up to four recent pitch/rhythm events, source-melody features, harmony, and metrical position; it does not plan complete themes or guarantee long-range phrase development. The current corpus is four authored solos from Autumn Leaves and All of Me.