Although ZIPI provided many outstanding new features, they did not line up well with existing MIDI-based implementations. The unusual addressing scheme which required substantial increase in complexity was the main factor in the lack of its adoption. Maintaining 1,016,127 individual synthesis states was far beyond the capabilities of synth hardware of the time, even though ZIPI developers hinted that there would be some practical limits upon the number of simultaneously available programs and notes. In comparison, MIDI defined only 16 channels that accumulated common channel control messages like program change, volume and pitch, and most digital synthesizers of the time could only provide from 12 to 128 simultaneously sounding notes.