QjackCtl is a simple Qt application to control the JACK sound server
daemon.  It provides a simple GUI dialog for setting several JACK daemon
parameters, which are properly saved between sessions, and a way
to control of the status of the audio server daemon.  With time,
this primordial interface has become richer by including a enhanced
patchbay and connection control features.

WWW: http://qjackctl.sourceforge.net/