The Rhythm Composer TR-707 is a fully programmable rhythm machine which allows you to program 4 Rhythm Tracks (altogether 998 bars) from up to 64 kinds of user-created Rhythm Patterns. Each of the digital drum voices has a separate output jack for individual mixing. For programming, it features a shuffle and flam effect and its programming abilities are very impressive.

An optional memory cartridge plugs directly into the Composer for instantaneous loading and saving, expanding the memory by three times. A display window helps your operation to a great extent. MIDI Bus on the rear panel interfaces with other MIDI devices to allow control of several instruments.