Equalizer in Pulseaudio

I know of 2 options how to use equalizer
1) separate equalizer app
2) via loadable pulseaudio (PA) module

Ad 1)
outdated, seems like app is no longer supported and most of time not working due to various conflicts with PA or dbus

Ad 2)
The way I use. This way depends on loadable modules for PA. PA supports many loadable modules, for more info check link at the bottom

[12:54:25] root@localhost ~# ls -la /usr/lib64/pulse-12.2/modules/module-ladspa-sink.so
-rwxr-xr-x. 1 root root 56K 2018/07/16 19:41:42 /usr/lib64/pulse-12.2/modules/module-ladspa-sink.so
[12:54:18] root@localhost ~# rpm -qf /usr/lib64/pulse-12.2/modules/module-ladspa-sink.so
pulseaudio-12.2-1.fc29.x86_64

How to setup Pulseaudio :
all adjustments in config file /etc/pulse/default.pa
General syntax :
load-module module-ladspa-sink sink_name=ladspa_out sink_master=AUDIO_SINK plugin=mbeq_1197 label=mbeq control=10_VALUES_SEPARATED_BY_COMMAS

We need to customize 2 fields: AUDIO_SINK and 10_VALUES_SEPARATED_BY_COMMAS. It will be clarified later on
So now we will add 3 equalizers to config file /etc/pulse/default.pa

load-module module-ladspa-sink sink_name=ladspa_out sink_master=alsa_output.pci-0000_00_1f.3.analog-stereo plugin=mbeq_1197 label=mbeq control=4.8,4.8,3.5,2.5,0.0,-7.0,-14.0,-10.0,-10.0,-8.0,1.0,1.0,5.2,7.7,9.5
load-module module-ladspa-sink sink_name=ladspa_out2 sink_master=alsa_output.pci-0000_00_1f.3.analog-stereo plugin=mbeq_1197 label=mbeq control=7.8,5.8,4.0,2.5,0.0,0,0,0,0,0,1.0,1.0,5.2,7.7,9.5
load-module module-ladspa-sink sink_name=ladspa_out3 sink_master=alsa_output.pci-0000_00_1f.3.analog-stereo plugin=mbeq_1197 label=mbeq control=2,2,1.75,1.5,0.0,0,0,0,0,0,1.0,1.0,1.25,1.5,2

Modules can be configured in mentioned config file, so they will be loaded automatically on PA start OR they can be loaded using pactl:

pactl load-module module-ladspa-sink sink_name=ladspa_out sink_master=alsa_output.pci-0000_00_1f.3.analog-stereo plugin=mbeq_1197 label=mbeq control=4.8,4.8,3.5,2.5,0.0,-7.0,-14.0,-10.0,-10.0,-8.0,1.0,1
.0,5.2,7.7,9.5

When modules are loaded u can switch one of these 3 equalizations directly in Pavucontrol utility – on 1st tab Playback, for different apps u can choose audio source -1st one is usually you soundcard (unmodified sound) OR 3x LADSPA Plugin Multiband EQ.. (“equalized” sound).

 

how to find out AUDIO_SINK
[14:29:39] root@localhost ~# sudo -u pulse sh -c "pactl list sinks | grep Name"
Name: null
Name: alsa_output.pci-0000_00_1f.3.analog-stereo

 

how to find out 10_VALUES_SEPARATED_BY_COMMAS

this values were taken originally from Equalizer app at the time when it was yet working, however u can choose any values, try to stick in range +15..-15

 

More info about module module-ladspa-sink
at https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/Modules/#index47h3