Approach for recording using jack soundcard about soundcard HOT 1 OPEN

The aim of this library is to implement the "native" audio interface of each operating system. Critically, I want to be able to select the system's default sound card, and get the same thing every other app is using. At this time, this means pulse, not jack.

That said, each implementation (Windows WASAPI, MacOS CoreAudio, Linux Pulseaudio) is technically entirely separate. They just happen to implement the same API. I wouldn't mind adding additional implementations for e.g. Jack, if you were to program one.

However, Jack has a very specific use case, of low latency and flexible routing, and Python is not a very good fit for these sorts of applications. The garbage collector and the need to use Numpy and the lack of free threading limits our low-latency capabilities. If you're going to do any processing whatsoever, you're typically looking at an internal latency of at least 10ms, at which point Jack doesn't provide much benefit over pulse any more. So it's not a great fit for soundcard in general, I'm afraid.

from soundcard.