Instance Method


Initializes a bus object with a specific format.


- (instancetype)initWithFormat:(AVAudioFormat *)format error:(NSError * _Nullable *)outError;



The initial audio format.


Returns an error if the operation failed, or nil if it succeeded.

Return Value

A newly-initialized bus object, or nil if the operation failed.


Audio units can generally be expected to support the AVAudioFormat standard format (deinterleaved 32-bit float), at any sample rate.

Channel counts can be more complex. See the channelCapabilities reference for a more complete discussion.

Initialization will fail and return an error if the specified format is unsupported for the bus.

See Also

Audio Unit Implementations


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


The maximum number of channels supported for this bus.

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