Sequential Prophet 5, Prophet 10Released in 1978
The Prophet 5 is an iconic analog polysynth, and was one of the first synths to use RAM storage for presets. It has 5-note polyphony, with two oscillators per voice. Rev 1 P5's are very rare (and rather unreliable), and were hand-built. Rev 2's are highly sought after, as they use SSM filter chips and have a huge sound. With Rev 3, CEM filters were used, some circuits were redesigned, and the sound was not quite as big.
A Prophet 10 is essentially two Prophet 5's -with two keyboards - built into one unit.