AppleOutputBackend

Apple output: CoreAudio, on CoreAudio's own clock.

The pairing is the whole reason this object exists. CoreAudioSink reports when a buffer becomes audible as a host time and requires AppleHostClock, and the engine anchors its master clock to that instant, so both sides have to read the same time base. Handing the engine one object rather than a clock and a factory separately makes the mismatch unassemblable instead of merely checked.

It supplies no renderer. A renderer draws into a view or a window that only the application owns, so the application builds one and attaches it, which is legal at any time, including while playing.