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# supportedChannelCounts

An array of numbers indicating the supported number of channels for this bus.

```
var supportedChannelCounts: [NSNumber]? { get set }
```

## Discussion

If the value of this property is `nil`, then any number less than or equal to the value of [`maximumChannelCount`](/documentation/AudioToolbox/AUAudioUnitBus/maximumChannelCount) is supported. If setting a new value on this property makes the current bus format unsupported, then the value of [`format`](/documentation/AudioToolbox/AUAudioUnitBus/format) is set to `nil`.

The default value is `nil`.

---

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