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# init(audioComponentDescription:)

Creates a MIDI instrument audio unit with the component description you specify.

```
init(audioComponentDescription description: AudioComponentDescription)
```

## Parameters

`description`

The description of the audio component.

## Return Value

A new [`AVAudioUnitMIDIInstrument`](/documentation/AVFAudio/AVAudioUnitMIDIInstrument) instance.

## Discussion

The component type must be `kAudioUnitType_MusicDevice` or `kAudioUnitType_RemoteInstrument`.

---

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