 It was released in 1981 with a list price of US$3,295 (¥430,000 JPY) and was the successor to the MC-8, which in 1977 was the first microprocessor-based digital sequencer.Like its predecessor, the MC-4 is a polyphonic CV/Gate sequencer.This sequencer was released before the advent of MIDI, and viewed by some composers to have more accurate timing.