MC 4

TheRoland MC-4 MicroComposerwas an earlymicroprocessor-basedmusic sequencerreleased byRoland Corporation. It could be programmed using the ten key numeric keyboard or asynthesizerkeyboard using the keyboard's control voltage and gate outputs. It was released in 1981 with a list price ofUS$3,295(equivalent to $11,400 in 2024) (¥430,000JPY) and was the successor to theMC-8, which in 1977 was the first microprocessor-based digital sequencer.Like its predecessor, the MC-4 is apolyphonicCV/Gatesequencer.