# setTrackVolume

[Built-ins](README.md)

Canonical ID: `media.setTrackVolume`. Nederlands: `zetSpoorVolume`.

Sets a named track volume from 0 to 100. It can prepare a track before playback starts; master and track gains multiply.

## Signature

```text
setTrackVolume(track, percentage)
```

## Example

```pliro
# language: en
setTrackVolume("bass", 30)
startMelody("bass", "C3:2 G2:2", 120, "pluck")
wait(2)
```

## Values and host support

Audio calls return `None` and do not block. Volumes are finite numbers from 0 to 100. Track names are case-sensitive text, 1–64 Unicode code points, with no control characters and not only whitespace. There are at most 16 named tracks and 32 simultaneous voices. Notes use `C4`, `C#4`, `Bb3` or `R`; a score adds `:beats`. Beats range from 1/64 to 64; tempo is 20–400. Instruments include `chip`, `bell`, `pluck`, `flute`, `drums` and the 128 exact `gm.` instrument IDs in the instrument picker. See the music guide for score bounds and lifetime.

Sounds use packaged project paths, not arbitrary files or URLs. A WAV example requires that asset in the `.bipli` project. Native Windows/Linux/Pi supports bounded PCM WAV; other codecs depend on the IDE/browser. Synthesis requires no asset. The text-only CLI and phone preview do not play this audio.

[Music and sound](../guides/music.md)