Alsaequal on debian 7 wheezy with MPD

Alsaequal is an equalizer for the ALSA soundsystem that can be used from command line. It gives system-wide equalizer capability to your Debian system.

Tested on Debian 7.4 Wheezy 4/4/2014

This guide requires you have MPD installed and working with alsa

Download Alsaequal

Download File: alsaequal-0.6.tar.bz2

Make and Install alsaequal

• Get Dependencies

aptitude install build-essential caps libasound2-dev libasound2-plugins

• Switch to home directory and download alsaequal

wget http://www.thedigitalmachine.net/tools/alsaequal-0.6.tar.bz2

• Extract alsaequal, enter directory

tar xf alsaequal-0.6.tar.bz2
cd alsaequal

• Make soft link to alsa-lib for alsaequal make process

ln -sf /usr/lib/i386-linux-gnu/alsa-lib /usr/lib/alsa-lib

• Run the make processes

make clean
make
make install
make clean

• alsaequal is now installed if you had no errors

Apply alsaequal at boot

• edit your ~/.asoundrc (make it if it doesnt exist)

nano ~/.asoundrc

• Add these lines

ctl.equal {
     type equal;
   }
   pcm.plugequal {
     type equal;
     # Modify the line below if you don't
     # want to use sound card 0.
     slave.pcm "plug:dmix";
   }
   # pcm.equal {
     # Or if you want the equalizer to be your
     # default soundcard uncomment the following
     # line and comment the above line.
   pcm.!default {
     type plug;
     slave.pcm plugequal;
   }

Link MPD with alsaequal

• for this you just need to modify your primary alsa device in /etc/mpd.conf to be like so:

audio_output {
 type		"alsa"
 name		"My ALSA EQ"
 device		"plug:plugequal"
 mixer_type      "software"	# optional
 mixer_device	"default"	# optional
 mixer_control	"PCM"		# optional
 mixer_index	"0"		# optional
 use_mmap	"yes"
}

Restart and check alsaequal

• Alsaequal should now be installed and working, try running it

alsa force-reload
service mpd restart
alsamixer -D equal

• If you are using root user change user in mpd.conf to root

Troubleshooting

1. A bad idea so says everyone basically, but in /etc/mpd.conf I had to change user to root for this to work. It is probably because I log in a root more than I should...

External Resources

• Debian forums - The install and make of alsaequal
• Crunchbang - Solved one of the problems I had
• Setting up MPD with alsaequal - Just the MPD info
• Debian forums - Solved a problem in the make process with missing alsa-lib
• The digital Machine - Alsaequal page about Ubuntu but has a download for it