I have installed alsaequal on a Raspberry Pi 4 B+ running Raspian and Snapclient (Linux snapclient 6.1.21-v8+ #1642 SMP PREEMPT Mon Apr 3 17:24:16 BST 2023 aarch64 GNU/Linux).
When I run:
speaker-test -D equal
the speaker test works and alsa equaliser can control the audio output using alsamixer -D equal.
When I list the audio devices available to Snapclient with:
snapclient -l
I get:
0: null
Discard all samples (playback) or generate zero samples (capture)
1: plugequal
2: equal
3: hw:CARD=sndrpihifiberry,DEV=0
snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi pcm512x-hifi-0
Direct hardware device without any conversions
4: plughw:CARD=sndrpihifiberry,DEV=0
snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi pcm512x-hifi-0
Hardware device with all software conversions
5: default:CARD=sndrpihifiberry
snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi pcm512x-hifi-0
Default Audio Device
6: sysdefault:CARD=sndrpihifiberry
snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi pcm512x-hifi-0
Default Audio Device
7: dmix:CARD=sndrpihifiberry,DEV=0
snd_rpi_hifiberry_dacplus, HiFiBerry DAC+ HiFi pcm512x-hifi-0
Direct sample mixing device
but if I try to run:
snapclient -s 2
I get an error:
2024-02-12 11-10-17.610 [Info] (Snapclient) Version 0.27.0, revision 54a3d862
2024-02-12 11-10-17.627 [Info] (Avahi) (Browser) NEW: service 'Snapcast' of type '_snapcast._tcp' in domain 'local'
2024-02-12 11-10-17.628 [Info] (Avahi) (Browser) CACHE_EXHAUSTED
2024-02-12 11-10-18.075 [Info] (Avahi) Service 'Snapcast' of type '_snapcast._tcp' in domain 'local':
2024-02-12 11-10-18.076 [Info] (Avahi) snapserver.local:1704 (192.168.0.237)
2024-02-12 11-10-18.080 [Info] (Controller) Found server 192.168.0.237:1704
2024-02-12 11-10-18.080 [Info] (Connection) Resolving host IP for: 192.168.0.237
2024-02-12 11-10-18.081 [Info] (Connection) Connecting
2024-02-12 11-10-18.099 [Notice] (Connection) Connected to 192.168.0.237
2024-02-12 11-10-18.099 [Info] (Connection) My MAC: "d8:3a:dd:8e:4b:58", socket: 8
2024-02-12 11-10-18.301 [Info] (Controller) ServerSettings - buffer: 1000, latency: 0, volume: 48, muted: 0
2024-02-12 11-10-18.302 [Info] (Controller) Codec: flac, sampleformat: 44100:16:2
2024-02-12 11-10-18.302 [Info] (Player) Player name: alsa, device: equal, description: <none>, idx: 2, sharing mode: unspecified, parameters: <none>
2024-02-12 11-10-18.302 [Info] (Player) Mixer mode: software, parameters: <none>
2024-02-12 11-10-18.302 [Info] (Player) Sampleformat: 44100:16:2, stream: 44100:16:2
2024-02-12 11-10-18.302 [Info] (Alsa) Using default buffer_time: 80 ms, default fragments: 4
ALSA lib dlmisc.c:339:(snd_dlobj_cache_get0) Cannot open shared library libasound_module_pcm_equal.so (/lib/arm-linux-gnueabihf/alsa-lib/libasound_module_pcm_equal.so: cannot open shared object file: No such file or directory)
2024-02-12 11-10-18.303 [Error] (Alsa) Exception: Can't open equal, error: No such device or address, code: -6
2024-02-12 11-10-18.304 [Fatal] (Snapclient) Exception: Can't open equal, error: No such device or address
2024-02-12 11-10-18.304 [Notice] (Snapclient) Snapclient terminated.
I checked for libasound_module_pcm_equal.so and it can be found in /lib/aarch64-linux-gnu/alsa-lib/ but for some reason, Snapclient is trying to find it in /lib/arm-linux-gnueabihf/alsa-lib/
If I try and add a link:
sudo ln -s /lib/aarch64-linux-gnu/alsa-lib/libasound_module_* /lib/arm-linux-gnueabihf/alsa-lib/
I get the error:
ALSA lib dlmisc.c:339:(snd_dlobj_cache_get0) Cannot open shared library libasound_module_pcm_equal.so (/lib/arm-linux-gnueabihf/alsa-lib/libasound_module_pcm_equal.so: wrong ELF class: ELFCLASS64)
My /etc/asound.conf looks like this:
ctl.equal {
type equal;
}
pcm.plugequal {
type equal;
#slave.pcm "plughw:0,0";
slave.pcm "plug:dmix"
}
pcm.equal {
type plug;
slave.pcm plugequal;
}
Any ideas how I can fix this?
Thank you.
So I managed to figure this out. I also realised I had an error in my /etc/asound.conf file in the original post, but I set it to:
pcm.!default {
type plug
slave.pcm plugequal;
}
ctl.!default {
type hw card 0
}
ctl.equal {
type equal;
}
pcm.plugequal {
type equal;
slave.pcm "plughw:0,0";
}
pcm.equal {
type plug;
slave.pcm plugequal;
}
As per the instruction here: https://www.hifiberry.com/docs/software/guide-adding-equalization-using-alsaeq/
Otherwise, since I had installed the armhf version of snapclient, I also needed to install the armhf version of both libasound2-plugin-equal and alsa-utils found here:
After that, I could start snapclient using equal as the soundcard and then adjust the output using:
alsamixer -D equal
I did also encounter the following error:
/home/pi/.alsaequal.bin is the wrong length.
[Error] (Alsa) Exception: Can't open equal, error: Operation not permitted, code: -1
Not sure if this came about from all my tinkering but I deleted /home/pi/.alsaequal.bin and the error went away.