The polyphonic, programmable analog OB-X synthesizer was released by Oberheim in 1979. It was available in 4-, 6-, and 8-voice configurations. It even offered 32 program memory slots, polyphonic portamento, and polyphonic sample-and-hold. The 8-voice version would have set you back $5,995 at the time. MIDI? It was still a few years off, being first introduced on the Sequential Circuits Prophet 600 in 1983.