Qsampler is a linuxsampler GUI front-end application written in C++ around the Qt4 toolkit using Qt Designer. For the moment it just wraps the client interface of LinuxSampler Control Protocol (LSCP)
JACK Audio Connection Kit – Qt GUI Interface: A simple Qt application to control the JACK server daemon. Written in C++ around the Qt framework for X11, most exclusively using Qt Designer. Provides a simple GUI dialog for setting several JACK server parameters.
This program is an audio player, written with the help of the Qt library. The user interface is similar to winamp or xmms. An alternative user interface is also available.