TiMidity++ is a software synthesizer. It can play MIDI files by converting them into PCM waveform data or other various audio file formats. To add JACK support, install jack-audio-connection-kit and build with: JACK=yes ./TiMidity++.SlackBuild To add speex support, install speex and build with: SPEEX=yes ./TiMidity++.SlackBuild To use Xaw3d in Xaw interface, build with: XAW3D=yes ./TiMidity++.SlackBuild TiMidity++ can also be run as an ALSA sequencer client. To do this, make /etc/rc.d/rc.timidity executable and add this line to /etc/rc.d/rc.local: /etc/rc.d/rc.timidity start You will need a set of instrument patch files or soundbank fonts for TiMidity++ to be of any use. The freepats and eawpats packages both provide a set of patch files, as well as the fluid-soundfont package, so one of those will be needed.