Should DAW (Bitwig Studio) users on CachyOS avoid KDE Plasma DE?

[indy]

TL;DR
For Bitwig Studio users, I suggest CachyOS Gnome DE, configure Bitwig to use ALSA, not pipewire, to get the minimum latency of around 6ms.

With kernel 6.12 and sched-ext(s), one can achieve amazingly low audio latency in Bitwig Studio without sample drops causing digital distortion. However, CachyOS with KDE Plasma DE performs worse at buffer=64 samples and sample rate 48000 Hz. Gnome DE has no issues. I tested this on fresh installs with CachyOS December ISO using the flash sched-ext.

Fresh install with KDE Plasma DE

Cosmic installed with KDE Plasma DE

Fresh install with Gnome DE
pipewire

ALSA

Fresh install with Xfce DE

System info

If you use a Linux DAW, I recommend CachyOS, sched-ext rusty, and Gnome DE (Alpha-Cosmic appears to be better).

[Danny_Barron]

Sound system shouldn’t really have anything to do with DE, however, that’s just an opinion.
Sound should be just kernel and pipewire or pulse. Though maybe that’s not true, since Plasma can mute sound ? (not sure)

[nutcase]

Hmm, was ananicy-cpp disabled during testing?

[indy]

Yes @nutcase .

[indy]

Agree @Danny_Barron. My theory is that it is the way Plasma and pipewire work. My sound interface has a ‘pro audio’ option in the Plasma Sounds setting, which Gnome does not give. I do not know much about pipewire configurations at a deeper level.

[indy]

Merry Christmas to you, too boss

I freshly installed CachyOS with Xfce rather than adding it to the existing one. No distortion of audio when buffer set at 64.

scx_flash

scx_rusty

Xfce is good.

[vancouver]

Out of curiosity,
what latency do you get with such a low buffer size?

I used to use Gnome and Harrison Mixbus 10 but have recently reverted that PC to W11 as it seems to handle USB for MIDI better.

[indy]

Playing the MIDI keys feels instant. Configuration window states 1.33ms.

Also asked chatGPT:

So, 1.33 ms stated in the configuration window may not be accurate.

Setting the driver model to ALSA block size gets stuck in 256. Input and output latency becomes 256. So, that setup gives the best latency of approx 6 ms. That is amazing.

[indy]

@vancouver

I used to use Gnome and Harrison Mixbus 10 but have recently reverted that PC to W11 as it seems to handle USB for MIDI better.

I have Windows and a M1 Macbook. I will run Bitwig Studio demo on all to compare the Oses. I gotta find time

[indy]

True. I find MacOs is the most straightforward forward, and there is a ton of software.

[indy]

@altman

Wonder if you try the RT kernel version

Thanks for the suggestion, and I did. It is not as good with the default kernel with sched-ext.

Linux cachyos-x8664 6.12.6-1-cachyos-rt-bore-lto_No_sched-ext

Linux cachyos-x8664 6.12.6-2-cachyos_rusty

[inffy]

The default kernel has already the rt patch that was finally merged in 6.12 and its different thing than the rt kernel.

The default kernel should be way better for realtime stuff, especially music prod

[vancouver]

Thank you for your replies. I found that, over the years, hardware (as in audio interface) also makes a difference.

I have a bit of free time over the next few days and might record a few Christmas songs on CachyOS. If I can use the USB cable for MIDI, I would consider switching back … maybe.

[indy]

I hope you enjoy recording!

[deex]

@indy

Also asked chatGPT:

Never ask any LLM like ChatGPT and all the others to calculate or reason anything.

They are text generators operating on statistical probability models, not something scientific or something able to reason or calculate or have numerical or factual hard knowledge.

It’s all just textual probabilities, nothing “hard” or relieable!
So they are good at text work, because it does not matter what they exactly tell but awful on anything with facts, numbers and reasonings.

[indy]

Thanks for the advice @deex . You made some valid points. These large language models can be useful, too.