# startMelody

[Built-ins](README.md)

Canonical ID: `music.startMelody`. Nederlands: `startMelodie`.

Starts a synthesized score on a named track without blocking the program. The score can contain notes, rests and chords. Use [startOrchestra](startOrchestra.md) when several instrument parts must start together.

## Signature

```text
startMelody(track, score, tempo = 120, instrument = "chip", loop = false, tempoChanges = [])
```

## Example

```pliro
# language: en
startMelody("theme", "C4+E4+G4:2 F4+A4+C5:2", 120, "gm.acoustic-grand-piano", false, [[2, 90]])
wait(3)
```

The second chord starts after two beats, when the tempo changes from 120 to 90 BPM.

## Score and tempo

A score uses space-separated tokens such as `C4:1`, `C#4:0.5`, `Bb3:2`, `R:1` or `C4+E4+G4:2`. Chords have up to eight distinct pitches and one shared duration. Each event lasts 1/64–64 beats; a score contains 1–4096 events and lasts at most 4096 beats.

Choose `chip`, `bell`, `pluck`, `flute`, `drums` or an exact ID from the 128 `gm.` instruments in the block/composer picker. Pitches must fit MIDI 0–127; drums use B1–A5.

The optional final `tempoChanges` list contains up to 256 `[beat, BPM]` pairs. Beat positions start at zero, increase strictly and fall before the score ends. Tempo must be 20–400 BPM. An empty list keeps a constant tempo; a marker at zero overrides the starting tempo. Held notes remain held across a change. Looping repeats the whole score and its tempo changes.

## Tracks and host support

The call returns `None`. Track names are case-sensitive text, 1–64 Unicode code points, nonblank and without control characters. Starting on an existing name replaces its audio while preserving its volume. Use `setTrackVolume` or `stopTrack` to control it. There are at most 16 named tracks and 32 simultaneous sounding notes.

Keep a looping track alive with events, a game loop or a positive `wait`. Normal program completion stops loops; Stop/Reset clean up playback. Synthesized audio requires no asset and works in the IDE, playground and supported native Windows/Linux/Raspberry Pi exports. The text-only CLI and phone preview do not play it.

The [melody editor and composer](../guides/music.md) edit ordinary source scores. Optional MIDI keyboard input belongs to the editor; this function does not access MIDI devices or files.