Explore Symbolic

structural / Symbolic

Song form

A 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).

How it works

This object can carry concrete values or a musical interpretation, depending on its notation.

It groups note 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

Canonical: semicolon-separated `Label: progression` sections; each progression is a comma-separated chord chart. Repeats are allowed (a chorus can recur).

  • Intro: C,G; Verse: C,G,Am,F; Chorus: F,C,G,G; Verse: C,G,Am,F; Chorus: F,C,G,G
  • A: Dm7,G7,Cmaj7; A: Dm7,G7,Cmaj7; B: Am7,D7,Gmaj7; A: Dm7,G7,Cmaj7

midi sections

Same structure with MIDI chord sets: `Label: set,set,…` where a set is dash-joined MIDI numbers.

  • Verse: 60-64-67,67-71-74,57-60-64,53-57-60; Chorus: 53-57-60,60-64-67
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

Pc Set SequenceAn ordered sequence of pitch class sets that may contain duplicatesPoint Set SequenceAn ordered sequence of point-sets that may contain duplicatesPc song formA 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.Point 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.Note sequenceAn ordered line of notes and optional rests. Adding durations makes its rhythmic placement explicit.ScoreA polyphonic texture — several voices (temporalized lines / tracks) sounding at once over a shared timeline. The simultaneous counterpart of a note-set: where a note-set stacks single notes into a chord, a score stacks whole lines. Its `groupOf` is note-sequence. Collapse the voices at each instant and you get a chord progression (note-set-sequence) — the resulting chord qualities of the simultaneous notes; conversely, a chord progression can be voice-led into a score. Strip pitch and it becomes a point-score (key-independent counterpoint).
Sources and playback

Concept descriptions and examples were adapted from Codex Music Mono’s typed catalog and concept examples. The Code Sequencer plays MIDI through a connected instrument; Symbolic does not synthesize sound.