Realtime editing and performance of digital audio tracks

A realtime system for performance of a remixed version of audio data representing multiple parts of an original composition and organized as a plurality of individual original tracks each representing a different part and having shared beats and measures defining a common tempo to be used to synchronize the individual tracks to thereby re-create the original composition, the system comprising:

• a respective plurality of stored alternative audio tracks for each of several related parts of the original composition, each alternative track being synchronized in tempo with a corresponding track of the original composition;
• a respective plurality of stored parameters for each of several defined effects;
• track selection means for independently selecting a particular alternative track to be swapped out for a corresponding original track at a designated transition point during a performance of the original composition;
• and
• effects selection means for independently selecting a particular defined effect to be applied at a designated insertion point during the performance of the original composition, wherein the defined effects include at least three different stutter gestures, each gesture being selectable by movement of a user input device in a respective different cardinal direction.