How to create an AUAudioUnit that implements multiple audio devices?

Question

In the Apple docs for creating the AUAudio module (here: https://developer.apple.com/documentation/audiotoolbox/auaudiounit/1387570-initwithcomponentdescription ) they claim that

A subclass of a single audio device can implement multiple audio devices — for example, an effect that can also function as a generator or cluster of related effects.

There are no examples of this online that I can find. Ideally, it would be nice if your answer / solution included Swift and AVAudioEngine, but I would gladly accept any answer that made me move in the right direction.

Thanks in advance.

Answer 1

, AVAudioUnit AVAudioEngine, Swift C GitHub :

https://github.com/hotpaw2/auv3test5

, Apple Swift , C, Objective C.

initWithComponentDescription: options: error:, , ( - switch ).