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1988 (Jan.)
Initially sold for ¥37,000
Lower end of the RX spectrum, the 120 was clearly built for people who just wanted an easy drum machine to provide rhythm when playing. There's no way to build patterns: instead the user can create songs using prebuilt patterns and their variations. However, even if everything is predetermined and controls for single percussions are clearly not made for live playing, the RX120 does have a MIDI in port, thus being able to be controlled (especially by a sequencer, where patterns can be created).
With 38 sounds on board that are pretty similar to what you'll find on other RX machines, it can be effectively used in a professional environment as expander just for the sounds.