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pta2002

Just tried it on NixOS, had no idea it was so fleshed out already! Thought it'd be full of bugs but was pleasantly surprised, it just worked. No issues with compatibility, extremely low latency and has JACK and PulseAudio shims, so everything works out of the box, including pro audio stuff like Reaper and Ardour. And thanks to the JACK shim I can patch around the outputs with qjackctl. This is compared to JACK, which I never managed to properly combine with PulseAudio.

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But does it work with the OSS shim for alsa shim for pulseaudio shim for jack shim for pipewire?

Jokes aside my first reaction upon hearing about pipewire was "oh no, not yet an other Linux audio API" but maybe a miracle will happen and it'll be the Chosen One.

I know that audio is hard but man the situation on Linux is such a terrible mess, not in small part because everybody reinvents the wheel instead of fixing the existing solutions. Jack is definitely the sanest of them all in my experience (haven't played with pipewire) but it's also not the most widely supported so I often run into frustrating issues with the compatibility layers.

> not in small part because everybody reinvents the wheel instead of fixing the existing solutions.

I'm using all of these reinventions. Wayland, systemd, flatpak, btrfs and soon pipewire. I'm absolutely loving linux right now. Everything works so nice in a way it will never on a distro with legacy tools. Some of these projects like flatpak have a few rough edges but the future is very bright for them and most problems seem very short term rather than architectural.

I also liked JACK the best. But was frustrated with compatibility layers.

Pipewire lets me use all the JACK tooling, but without needing a special compat layer to manage it. so for now, I'm pretty excited

Still havent figured out how to get anything working for video.

I gave JACK a try more than a decade ago, and I remember how cool it was to be able to pipe the audio from one application to the input of another (unrelated) app, possibly adding effects or transformations in between. But JACK never became "mainstream" so I never got to use it for anything serious, but I miss the flexibility it offered even for non professional use-cases. What I wonder is if PipeWire will allow this kind of routing or patching of audio streams as well.

It does, exactly the same way as JACK, and you can even do it with pulseaudio apps! I could pipe audio from a firefox tab through guitarix (guitar amp emulator) into a second firefox tab if I wanted to. With just JACK or just Pulse this wouldn't be possible. And if I understand it correctly, it should work for video streams too. I'm imagining piping a screenshare through OBS before going into discord or something, should be very useful.

You can do that in Pulse, by using null sinks and monitor sources.

I see what you mean, still a lot more complicated than just dragging a "wire" in qjackctl though.

https://github.com/futpib/pagraphcontrol

It's not super polished, but you can do similar wire dragging here.

I'm running PipeWire on Arch and I can do it through `pw-jack carla`[1]. You can do surprisingly advanced stuff through the JACK compatibility.

[1] https://i.imgur.com/EFUxR41.png

Hey, it looks nice! But, are you required to be running JACK? I mean, isn't this routing capability part of the PipeWire's core?

No, I don't have jackd running. Launching something with `pw-jack` (AFAIK) makes that use the PipeWire libraries instead of the normal JACK ones. I think PipeWire has it's own internal graph that's compatible with ALSA, PulseAudio, and JACK, and that's how it can work with any program. Here's the output of `pw-dot` which is a PipeWire tool that dumps the graph: https://i.imgur.com/OMZCcmC.png

Thanks for the datapoint. I've been following https://github.com/NixOS/nixpkgs/issues/102547 and considering trying it out for a while.

Did you just set services.pipewire.pulse.enable=true?

https://search.nixos.org/options?channel=unstable&show=servi...

My major concern is that I use PulseEffects as a key component of my setup so I'll need to check if that works well with PipeWire. But the only way to be sure is to try it!

I also have Pipewire running on NixOS. This is what I recommend configuring:

  services.pipewire = {
    enable = true;
    alsa.enable = true;
    alsa.support32Bit = true;
    jack.enable = true;
    pulse.enable = true;
    socketActivation = true;
  };

That allows me to run pretty much any application that uses ALSA, JACK, or PulseAudio.

That gave me "services.pipewire.alsa" does not exist on 20.09; does this require unstable?

I believe so, I am on the unstable channel.

https://github.com/wwmm/pulseeffects#note-for-users-that-did... Pulseeffect has only support for Pipewire since version 5 and Pulseaudio in the legacy Pulseaudio branch

I didn't get to try it under PipeWire on my Arch laptop before that died the other day, but a friend had said PulseEffects is no longer such a massive CPU hog under PipeWire, so much so that they run it all the time now.

Interesting. I have PulseEffects running all of the time on PulseAudio and don't notice much CPU usage. However maybe that is because I only apply effects to the mic and it seems to disable itself when nothing is recording.

I just tried it on NixOS and the new version is already packaged and working.

> extremely low latency

How low is "extremely low", especially compared to JACK that I'm currently using when doing music production?

What latency do you get using JACK?

Not in front of the right computer, but I think it's around 15ms for a full roundtrip.

>This is compared to JACK, which I never managed to properly combine with PulseAudio.

Yeah making PulseAudio play nice with JACK seems to be tricky. Over time I configured it in four different environments (different Linux Distributions and/or Versions) and for each of them I had to do things (at least slightly) differently to get them to work.

Using JACK apps to route between PulseAudio apps under PipeWire is magic, as is being able to turn on external DACs after login and still be able to use them with JACK apps without restarting any software. Also PulseAudio not randomly switching to the wrong sample rate when I open pavucontrol is a blessing. (And it's so easy to setup, at least on Arch Linux.).

I have come to describe PW as like a superset of JACK and PulseAudio.

Also to note, #pipewire is very active on freenode, and wtay regularly drops into #lad.

I've first read about PipeWire about two months ago and I'd really love to try it. But! My setup is working and I'm really not the kind of person who likes to unnecessarily tamper with a smoothly running system. So I'll probably try it the next time I need to do a fresh install. Promise!

I found it tricky at first but got a mostly smooth setup on two machines now with wide variety of uses.

Definitely for day-to-day use the Ubuntu Studio app has actually been the most helpful (direct control / visibility into the Jack <-> PA bridging is great), or a combo of qjackctl and Carla for more Audio-focused stuff.

> Yeah making PulseAudio play nice with JACK seems to be tricky.

for me https://github.com/brummer10/pajackconnect has worked flawlessly... but I've switched to pipewire and I'm not looking back !

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