---
title: duration
framework: avfaudio
role: symbol
role_heading: Instance Property
path: avfaudio/avextendednoteonevent/duration
---

# duration

The duration of the event, in beats.

## Declaration

```swift
var duration: AVMusicTimeStamp { get set }
```

## See Also

### Configuring a Note On Event

- [midiNote](avfaudio/avextendednoteonevent/midinote.md)
- [velocity](avfaudio/avextendednoteonevent/velocity.md)
- [instrumentID](avfaudio/avextendednoteonevent/instrumentid.md)
- [groupID](avfaudio/avextendednoteonevent/groupid.md)