soundio/sequence

Sequencer

Create, export, and visualize music sequences in the soundio/sequence JSON format — a minimal, interoperable structure for timed musical events aligned with the Web Audio API, MIDI 1.0, and OSC.

Piano roll → sequence JSON

BPM

Time

1

·

·

·

2

·

·

·

3

·

·

·

4

·

·

·

B4

A♭4

A4

G♯4

G4

F♯4

F4

E4

D♯4

D4

C♯4

C4

B3

A♭3

A3

G♯3

G3

F♯3

F3

E3

D♯3

D3

C♯3

C3

soundio/sequence JSON output

{
  "name": "SoundLab Composition",
  "events": [
    [
      0,
      "meter",
      4,
      1
    ],
    [
      0,
      "rate",
      2,
      "step"
    ]
  ]
}

Format: [beat, "note", midiPitch, dynamic, duration] · rate = BPM/60 beats/sec · spec: soundio/sequence ↗

soundio/sequence spec·Event: [beat, type, ...params]·HSID = Harmonic Structure ID·rate 2 = 120 BPM·github.com/soundio/sequence ↗