Multichannel DSP/EQ on Linux

[concorde1]

Hi - I use a Topping DM7 8 channel DAC.

Is there a GUI software for DSP on Linux with Multichannel capability?

Or if no GUI available - can CamillaDSP do this?

I have looked at CamillaDSP - but have concerns:

• I would want 2x headphone profiles and 1x (speaker+subs) profile - how would I efficiently switch between them - use 3 separate config files and reload CamillaDSP service?
• Converting say, an AutoEQ profile, for a CamillaDSP config, would take a while
• But I would probably actually struggle to write a CamillaDSP config for (speakers+subs), because there are the following complications: involves sending stereo audio to 4 of 8 channels, of which Ch3 and Ch4 are both summed mono from 0.5*Ch1+0.5*Ch2; and after that, Ch1 and Ch2 have an EQ applied (and bass management delay), while Ch3 and Ch4 have a different EQ applied.

I can do these things on Equalizer APO on W10 of course. I use Linux most of the time though - it would be nice to have my full range setup working.

I could attempt the CamillaDSP config if anyone could steer me away from mistakes.

Any advice? Thanks

 

[voodooless]

Conversion of autoeq profiles:

GitHub - Ebert-Hanke/autoeq2camilladsp: Conveniently create CamillaDSP configurations for headphone listening with AutoEq correction data and options for Crossfeed etc.

Conveniently create CamillaDSP configurations for headphone listening with AutoEq correction data and options for Crossfeed etc. - Ebert-Hanke/autoeq2camilladsp

github.com

Web interface:

GitHub - HEnquist/camillagui-backend: Backend server for camillagui

Backend server for camillagui. Contribute to HEnquist/camillagui-backend development by creating an account on GitHub.

github.com

 

[concorde1]

Thank you for sharing the AutoEQ converter and GUI.

I found the GUI actually accepts EqAPO files, thankfully.

I've probably made a few mistakes in my config files: CamillaDSP service fails to start ; CamillaGUI service fails to start ; and I get an SELinux alert

I put "2 channels" for everything because my source audio will be 2 channels, and it seems it has to be the same in all config files?

I also have a Pipewire conf which allows only 48 kHz (my chosen sample rate).

Blocked out my username, but in these images you can see the paths / file names, and their contents.

Note I used "aplay -l" and found the Loopback is card #4, and devices #0 and #1; and my dac is card #0 and device #0.

If anyone can help - would be much appreciated!

 

[somebodyelse]

There's also CamillaNode 2 which has AutoEQ integrated - although I'm not sure whether it's being updated any more.

 

[phofman]

Note I used "aplay -l" and found the Loopback is card #4, and devices #0 and #1; and my dac is card #0 and device #0.

The safe rule is to use card names instead of card IDs in alsa device name strings.

 

[somebodyelse]

Yes - the card ID numbers are assigned in detection order, so if you attach a new device after booting, change the config for it then reboot you may find the card numbers have changed so the config is no longer behaving as intended. The card names will remain the same, although I'm not certain what happens if you have 2 of the same device.

 

[phofman]

Card IDs and names can be customized by udev rules - e.g. section "Identify two identical audio devices" in https://alsa.opensrc.org/Udev#Identify_two_identical_audio_devices or https://www.alsa-project.org/wiki/Changing_card_IDs_with_udev

 

[concorde1]

So I started from scratch with CamillaDSP + CamillaGUI.

This time I found and followed this instruction from mdsimon2's RPi+CamillaDSP guide (even though I'm not using Raspberry Pi):

"See below for a brief explanation of the CamillaDSP flags applied in ExecStart of the service.


"-s camilladsp/statefile.yml" tells CamillaDSP a configuration will be specified via the GUI.


"-w" tells CamillaDSP to wait for a configuration to be applied via the GUI.


“-g-40” sets CamillaDSP volume control to -40 dB every time it starts to avoid accidentally playing something really loud after a system restart. If not using CamillaDSP volume control please delete “-g-40”.


"-p 1234" is needed to connect to the GUI.


"-o camilladsp/camilladsp.log" creates a log file that can be viewed in the GUI for troubleshooting. Verbosity of this log can be increased by adding "-l debug"."

CamillaDSP started successfully! And CamillaGUI is connected.

Some questions:
- If I start camilladsp.service (I'm just using executable right now), how do I pass these flags to it ( -s camilladsp/statefile.yml -w -p 1234 -o camilladsp/camilladsp.log ) ??

- One of mdsimon's camilladsp config for DAC's examples has 2in8out. But when I try that with a Mixer, I get an error in Pipeline. (Expected 8in.)
- I try 8in8out instead and just use the first 2in's
- But I get no sound output (nor sound shown in the GUI meters)
- Would someone be kind enough to look at settings below and suggest why no sound?

(In meantime I will see if it's something strange like the outputs on Topping DM7 being labelled 7 to 0 instead of 0 to 7 , lol)

EDIT: In my Linux sound - "Loopback Analog Stereo" is getting signal, but "DM7 Pro" is not.

 

[Thelo80]

Several Linux studio plugins parametric equalizer running at the same time and any gui for pipewire to connect them with each output