QSampler is a LinuxSampler GUI front-end application written in C++ around the Qt4 toolkit using Qt Designer. At the moment it just wraps as a client reference interface for the LinuxSampler Control Protocol (LSCP).
LinuxSampler is a work in progress. The goal is to produce a free, open source pure software audio sampler with professional grade features, comparable to both hardware and commercial Windows/Mac software samplers. The initial platform will be Linux because it is one of the most promising open source multimedia operating systems. Thanks to various kernel patches and the Jack Audio Connection Kit, Linux is currently able to deliver rock solid sub-5 millisecond MIDI-to-Audio response.