JackD
JackD "JACK Audio Connection Kit (or JACK) is a professional sound server API and pair of daemon implementations to provide real-time, low-latency connections for both audio and MIDI data between applications."
QjackCtl "QjackCtl is a simple Qt application to control the JACK sound server daemon, specific for the Linux Audio Desktop infrastructure."
Jamin "JAMin is the JACK Audio Connection Kit (JACK) Audio Mastering interface. JAMin is an open source application designed to perform professional audio mastering of stereo input streams. It uses LADSPA for digital signal processing (DSP)."