This early analog drum machine was used by the sonic visionary, Sly Stone. He called it “The Funk Box.” It only has 18 preset rhythms, pitch control, and triggers to play specific sounds.
Maestro Rhythm King MRK-1
Ace Tone Rhythm Ace FR-1
After the prototype rhythm Ace R-1 was shown at NAMM in 1964, Ace Tone released the Rhythm Ace FR-1. The first drum machine produced by a circuit called a diode matrix.