Jacob Duringer has been developing this keyboard instrument since 1981 - its a MIDI based controller which allows "one person to play a multiplicity of instruments strictly by skill with absolutely no utilization of tracking, dubbing, sequencing, programming or any other form of artificial assistance"
Essentially, as far as we can figure out, the 15x48 matrix of buttons laid out in four octave strips (x15 rows) allows for playing multiple instruments and timbral modification, each row can be a different instrument- presumably by careful programming of the receiving sound sources.
Clearly Jacob has devoted a considerable amount of time to his technique and his various performances and recourses can be found at Jacobduringer.com
Thanks to Leigh Kemp for the spot.
Seamless audio and MIDI switchover between computers