Solitaire's performance system was manufactured by Sequential Circuits (SCI). It consisted of the Sequential Circuits Six-Trak a six-voice, polyphonic, analogue synthesizer that was among the first MIDI instruments designed to be used with a computer.[4] The computer and software allowed Solitaire to program the Six-Trak sequencer and SCI's Drumtraks to form one of the earliest known MIDI-based [live] performance systems.[5] In 1984 the system used by Solitaire was said to "create instruments that have never been heard before," at that time "musicians [were] just beginning to tap its potential".[6] However, by modern computer standards the electronic rhythm section used by Solitaire was crude and had several limitations. For example, the SCI Model 64 Sequencer was limited to six voice sequencing. To play back more songs required sequences be saved to disk (loading of disk sequences had to be done live, on stage, during the performance).[4]