It will play songs and mix them together in the most simple way. Don't worry about doing complex settings only four settings are needed: Transition Type, Transition Time, Cut First and Cut Last seconds of each mixed song. +PLUS the interesting feature of using more than one sound card in the same computer. MP3DJ PRO can playback playlists in diferent sound cards, so more than one window of the program can be running at the same time, one window can be used as Previous Output (Head Set) and the other window for playing back to AIR. The idea is to hear what song to play next before actually play that song to air. This same feature can also be used for playing several channels (playlists) of mixed music from the same computer at the same time. Drag and drop files between windows to move songs from one channel to the other.