The usual command for it is qpaeq
.
Have you tried it ? I suppose Solus automatically edit the pulseaudio config file to load the modules when you install it, but if it doesn't, add :
load-module module-equalizer-sink
load-module module-dbus-protocol
to ~/.config/pulse/default.pa
(Can also be set on the default one in /etc/pulse/default.pa
but better make use of the .config folder)