The QY20 is a portable sequencer released by Yamaha in 1994. It has 8 tracks (4 for sequenceing and 4 accompaniment tracks (2 chord, bass and drums (8 different drum sets are available))).
For the sequencer you can use 100 different voices (guitars, brass, strings and many others) which can be recorded in real time- or in step-mode. The QY20 has an 1 octave keyboard included, but for home use you can plug any MIDI keyboard (even with attack dynamics (I hope this is the right word, if not please msg me the correct one) or any other MIDI device in. Unlike the QY70 it can not output complete songs directly, but has a MIDI output.

According to the orginially 650 $ expensive device, which is now out of production can be purchased for round about 150$ when used.