convolver sampling rate

[linuxonly]

Hi,

I used REW to generate wav impulse files for room correction, 44, 48 and 96 kHz. Imported into easyeffect convolver filter on Fedora 40 using the method described in

.

Best results so far compared to parametric equalizer. However, I have 44 and 48 kHz audio material, not to mention 5.1 encoded material (DTS, PCM, Dolby digital) to be processed by my Logitech Z906 (SPDIF).

Problem: easyeffects seems unable to pick the proper impulse file matching the sampling rate automatically and I have to load it manually each time audio material uses a different sampling rate than the preceding audio materiel. E.g. are my old mp3 (several GB) are sampled at 44, most videos audio at 48, older videos at 44. For the 5.1 material, just forget it for now, easyeffect being stereo only.

Of course when I use different sampling rate for audio material and impulse file, the result is off, far from optimal.

Fedora 40 is using pipewire for audio.

Any idea or suggestion?

 

[phofman]

Problem: easyeffects seems unable to pick the proper impulse file matching the sampling rate automatically and I have to load it manually each time audio material uses a different sampling rate than the preceding audio materiel.

IIUC this feature is not planned on implementing https://github.com/wwmm/easyeffects/issues/1558 . Therefore, have you considered configuring PW to run at a single samplerate, resampling all input clients to this common samplerate?

 

[ddude003]

@linuxonly you might take a look at the Hang Loose Convolver... It can do the filter matching to sample rate and is multichannel...

Hang Loose Convolver (HLC) - Accurate Sound

is a stereo and multichannel convolver designed to compare level matched convolution filters in real time with instant switching between filters. Bundled with Hang Loose Host.

accuratesound.ca

 

[linuxonly]

@linuxonly Hang Loose Convolver

Hang Loose Convolver (HLC) - Accurate Sound

is a stereo and multichannel convolver designed to compare level matched convolution filters in real time with instant switching between filters. Bundled with Hang Loose Host.

accuratesound.ca

Interesting, thanks. However it's only for Windows 10/11, Mac and Ubuntu. I'm on Fedora 40 / Debian 12.

Additionally, they don't support Windows 7, which means their perpetual licence worth nothing whenever you don't want to upgrade Windows for whatever reason.

 

[rattus]

HLC looks interesting albeit rather expensive. I just tried it on Debian 12 and the plugin host started and loaded but as I didn't want to spend too much time and I use JACK with configured EQ plugin as default audio, I didn't test it with audio.

Pipewire has a native filter chain module which may work for you. Documentation is sparse although I did manage to set up its parametric EQ filter on a different system and it works really well. It's all text file configuration so may be an exercise in nerdery to implement.

PipeWire - ArchWiki

wiki.archlinux.org

PipeWire: Filter-Chain

Multichannel Convolver filter help (#3875) · Issues · PipeWire / pipewire · GitLab

Hi. I'm trying REALLY trying and failing spectacularly. I could make it work stereo only.. Can someone please look at the following filter file and fix my mistake?...

gitlab.freedesktop.org

There should be an example file at /usr/share/pipewire/filter-chain/sink-virtual-surround-5.1-kemar.conf although you would need to modify it as shown in the above Gitlab link for proper 5.1 output.

 

[linuxonly]

@rattus

Those links are very interesting. Thanks a lot for that. Will definetely dig deeper. There is indeed a /usr/share/pipewire/filter-chain/sink-virtual-surround-5.1-kemar.conf on Fedora 40 however I have a priority right now: the newly released kernel 6.10.4 had pipewire to create nodes for hdmi a52/AC3 audio and I have nothing connected to hdmi. Those nodes are badly interfering with SPDIF as they have very similar names and it's not uncommon on reboot that I have no audio at all and have to restore from backup, so please excuse me if I'm slow to reply. Fixing that will likely take some time. Last kernel issue I wanted fixed took 3 months and it was a very simple one, like 2 lines of code. That's Fedora.

OTOH, I wonder how I would do to measure my FC, LFE, RR and RL channels as REW does not see them due to java limitation as John explained. The only way I see to output something to any of them is to use a 5.1 audio file. Food for thought. This data is required to build the filter chain.

Maybe buying that inexpensive HDMI to SPDIF converter now that I have (broken) pipewire hdmi nodes. I had a peek with pavucontrol and all the 6 channels are visible and could be tested. It doesn't work naturally, but the potential is there.

Fortunately, my Debian 12 system is analog stereo, so it's already configured using easyeffects. Glad to read HLC works on Debian, however easyeffects is dpoing the job allright already.

Best regards

 

[linuxonly]

Maybe buying that inexpensive HDMI to SPDIF converter now that I have (broken) pipewire hdmi nodes. I had a peek with pavucontrol and all the 6 channels are visible and could be tested. It doesn't work naturally, but the potential is there.

Tested. Does not work as I expected. I do have sound via hdmi, 5.1 passthrough works too, but as far as REW is concerned, it's still a stereo device. Returning the device because it only adds a supplemental level of complexity and adds nothing, not to mention the reconfiguration nightmare: alsa pipewire wireplumber kodi mpv mplayer vlc totem...