Ken Restivo &lt;ken(a)restivo.org&gt; writes: You're probably after ecasound: ecasound \ -i jack_auto -o jack_auto \ -el:fbdelay_5s,0.5,0.2,0.5 \ -el:freeverb3,0,0.12,0.05,0.1,0.5,0.9 By default that'll connect itself to alsa_pcm for input and output; if you want to automatically connect to a different host's ports, you can say something like "-i jack_auto,fluidsynth". The numeric parameters after the plugin name are in the same order that JACK Rack shows them in, so you can test your effects chain in JACK Rack then fairly straightforwardly translate it to an ecasound invocation. (Actually, perhaps JACK Rack should be able to give you an ecasound command line, or should come with a tool to run a saved rack with ecasound... that one's going on the projects list.) -- Adam Sampson &lt;ats(a)offog.org&gt; <http://offog.org/>