structural / Symbolic
Pc song form
A song form whose section progressions are octave-free (pitch-class) — the octaveless abstraction of a song-form. Keeps section labels, order, and harmony but drops register. Its `groupOf` is pc-set-sequence.
How it works
It identifies pitch independently of octave. Playback needs a register or voicing.
It groups pc set sequence objects in a defined order.
Written forms
Ways to write this concept
Each notation describes the same underlying object. Load a playable example to hear one MIDI realization in the Code Sequencer.
sections
Semicolon-separated `Label: progression` sections; each progression is comma-separated pc-sets (dash-joined pitch classes 0–11).
Verse: 0-4-7,7-11-2,9-0-4,5-9-0; Chorus: 5-9-0,0-4-7
Choose Load beside a convertible example to open its live player. Some catalog formats describe analysis or a display label and have no note realization yet.
Concept connections
Note Set SequenceAn ordered sequence of note sets (chords) that may contain duplicatesSong formA chord progression arranged by labeled section (intro, verse, chorus, bridge…) — the harmonic skeleton of a lead sheet or guitar-chord chart. An ordered, named sequence whose sections are chord progressions (its `groupOf` is note-set-sequence). Forget the labels/order and it becomes a collection of progressions; forget pitch and it becomes a point-song-form (a key-independent structural shape for comparing songs).Point Set SequenceAn ordered sequence of point-sets that may contain duplicatesPoint song formA song form reduced to non-pitch-specific shapes — section labels and order are kept, but each chord is a point-set (offsets, no key). This is the transposition-invariant structural fingerprint of a song: two songs in different keys with the same form land on the same point-song-form, so it is the natural representation for song-to-song similarity. Its `groupOf` is point-set-sequence.Pitch-class sequenceAn ordered line of pitch classes without fixed octaves. Choose registers to turn it into MIDI notes.Pc scoreAn octave-free polyphonic texture — simultaneous pc-sequences (lines of pitch classes). The octaveless abstraction of a score; keeps voice independence and harmony but drops register. Its `groupOf` is pc-sequence.