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# setFormat(_:)

Sets the bus’s audio format.

```
func setFormat(_ format: AVAudioFormat) throws
```

## Parameters

`format`

The desired audio format.

## Discussion

- <doc://com.apple.documentation/documentation/Swift/false> if the operation failed.

## Discussion

Audio units can generally be expected to support the <doc://com.apple.documentation/documentation/AVFAudio/AVAudioFormat> standard format (deinterleaved 32-bit float), at any sample rate.

Channel counts can be more complex. See the [`channelCapabilities`](/documentation/AudioToolbox/AUAudioUnit/channelCapabilities) reference for a more complete discussion.

> Handling Errors in Swift:
> In Swift, this method returns `Void` and is marked with the `throws` keyword to indicate that it throws an error in cases of failure.
> 
> You call this method in a `try` expression and handle any errors in the `catch` clauses of a `do` statement, as described in [Error Handling](https://docs.swift.org/swift-book/LanguageGuide/ErrorHandling.html) in [The Swift Programming Language](https://docs.swift.org/swift-book/) and `About Imported Cocoa Error Parameters`.

---

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