This little Yamaha QX21 is a digital sequencer released by Yamaha in 1986 as a follow-up to their previous QX7.
It's a 2-track sequencer that allows users to record and edit MIDI data. Recording and editing is done on track 1, where it can be exchanged or merged with track 2. It includes basic editing functions such as quantization, chaining, and inserting/deleting bars. Quantizing will store a track's information in a temporary buffer so the user can retrieve it later, and MIDI information can be removed per-channel.
This sweet little MIDI sequencer is lightly used, and we'll ship it to you super fast and super safe! Feel free to give us a call with any questions you may have about it!