Soundslice MusicXML exporter 2026-09-27 Vocal 4 0 major 4 4 G 2 C 4 4 quarter D -1 4 4 quarter flat E -1 4 4 quarter flat F 4 4 quarter G 4 4 quarter A 4 4 quarter B -1 4 4 quarter flat C 5 4 quarter