Audio System

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Audio System
Creating a network controled integrated music system for the entire space.
Audio system hacking


  • Fixed amp sound level at max we'll allow
  • Volume controlled with software
  • Software: The silent guy, MPD, Play Airwolf at due time --> combined using Jack
  • FM? Transmitter of reciever?


What we have available

  • A two channel amplifier. (Bert)
  • Two big speakers (Bert)
  • An avarage sized stereo (Kurt)
  • A small stereo (Impy)
  • A desktop with surround soundcard (Tom)

What we need

  • Jack to cinch cable
  • Cinch to cinch cable

The plan

(picture withboard)


  • Hang all speakers
  • Connect al speakers to there amplifiers
  • Rack mount the amplifier
  • Connect the amplifiers to the PC
  • Give the Audio System a fixed IP


  • Figure out what the s-control port does on the main amplifier.
  • Make the amplifier for the aft speakers powered only when music is played in that room.



MPD or Music player Deamon. Installed from repositories. Currently using Alsa as a sound backend. Needs to be coupled through Jack in order to make sound blend with sound from other sources.


There are a wide range of MPD clients available for a wide range of platforms. Feel free to add you experiences here:

  • Linux
    • Ario
    • Sonata
    • MPC (CLI) usage mpc --host= --port=6600 (play/stop/toggle/pause/next/prev/volume +xx/-xx/xx
  • iPhone
  • Android


Ampache: A web interface to stream once media laibrary and controle an MPD server. Installed from repo's. The deb instal package seems to have a bug so it is necessary to create a extra symlink before configuration can begin. This webinterface is available at Try it using user root and password ****** (the one we often use)

Ampache requires a MySQL databases. It was installed from repositories with as root password the one we use too often. The ampache user in the MySQL db is ampache, the password is """"

I'm not relay happy with this interface... Comments/Alternatives???


At this time the IP of the server is assigned by DHCP and may have changed. Fixed

Silent Guy

Playing Airwolf

The Airwolf theme should be played on midnight thurseday and friday. The file will come straight from YouTube. So we are not storing copyrighted information on our server. play airwolf from command line straight from youtube ignoring video:

vlc -I dummy --vout null

with additions for running in crontab

DISPLAY=:0.0 /usr/bin/vlc -I dummy --play-and-exit --vout null

full crontab line for now (still running more frequent to allow testing):

*/2 * * * * DISPLAY=:0.0 /usr/bin/vlc -I dummy --play-and-exit --vout null

now running in the sudo crontab (no need for user to be logged in) (not there yet)

*/2 * * * * exec whitespace DISPLAY=:0.0 /usr/bin/vlc -I dummy --play-and-exit --vout null

*/2 * * * * exec whitespace env DISPLAY=:0.0 /usr/bin/vlc-wrapper -I dummy --play-and-exit --vout null

finaly there use this line in /etc/crontab do NOT use sudo crontab -e I thought this had the same effect but it doesn't.

*/2 *   * * *   whitespace DISPLAY=:0.0 /usr/bin/vlc -I dummy --play-and-exit --vout null 
Doctor Who: (recent) (80's)


We will try to use Jack to make smooth combination of thes audio sources. Jack was installed from the repositories. It's currently working however audio quality is horrobly and now unusalble. Does anybody have some experience configuring Jack?