The AUAudioUnitV2Bridge class wraps a version 2 audio unit in an AUAudioUnit subclass.


@interface AUAudioUnitV2Bridge : AUAudioUnit


A version 3 audio unit may subclass the AUAudioUnitV2Bridge class. If so, the audio unit’s component description should refer to a registered component with a version 2 implementation by using a factory function. The bridge will instantiate the version 2 audio unit via the factory function and communicate with it using version 2 audio unit APIs.

Hosts should not access this class; it will be instantiated if needed when creating an audio unit.


Inherits From

See Also

Audio Unit v3

Hosting Audio Unit Extensions Using the AUv2 API

Update your existing Audio Unit v2 host app to load and use Audio Unit extensions.

Migrating Your Audio Unit Host to the AUv3 API

Update your Audio Unit (AU) host app to take advantage of the new features and capabilities of AUv3.


The AUAudioUnit class defines a host’s interface to an audio unit.


The AUAudioUnitBus class defines an input or output connection point on an audio unit.


The AUAudioUnitBusArray class defines a container for an audio unit’s input or output busses.


The AUAudioUnitPreset class describes an interface for custom parameter settings provided by the audio unit developer. These presets often produce a useful sound or starting point.


An AUParameter object represents a single audio unit parameter.


A parameter group object represents a group of related audio unit parameters.


An AUParameterNode object represents a node in an audio unit’s parameter tree. Nodes are instances of either an AUParameter or AUParameterGroup class.


An AUParameterTree object is a top-level group node, representing all of an audio unit’s parameters. An audio unit’s parameters are organized into a tree containing groups and parameters (groups may be nested).


Implement this protocol to create a version 3 audio unit.