Alsaequal is a real-time adjustable equalizer plugin for ALSA sound server. It can be adjusted using any ALSA compatible mixer, e.g. alsamixergui.
Alsaequal uses the Eq CAPS LADSPA Plugin for audio processing, actually alsaequal is a generic LADSPA plugin interface with real-time access to the LADSPA controls (the LADSPA plugin included with alsa doesn't allow for real-time controls) but it was developed for and only tested with Eq CAPS LADSPA plugin. You are welcome to try it with other plugins, it may work.
Download the latest version of the plugin and:
tar xvjf alsaequal-x.x.tar.bz2
sudo make install
After installing you will have to modify your local .asoundrc alsa configuration file, adding something like this. If you're not using sound card 0 modify "plughw:0,0" accordingly.
You can play audio through alsaequal by addressing the plugin by name, e.g.: mpg123 -a equal 06.Back_In_Black.mp3
You can adjust the frequency response of the equalizer by using any alsa mixer, e.g.: alsamixer -D equal
· CAPS LADSPA
· ALSA driver
What's New in This Release: [ read full changelog ]
· Improved support for additional LADSPA plugins, like mbeq, and improved performance.