The Oberheim Eight Voice was a monster of synthesizer, released in 1977, and was essentially eight monophonic Oberheim Synthesizer Expander Modules (SEMs) strapped together to give the 8 note polyphony of the instrument.

Famous users of this synth were many and varied including Tangerine Dream, Yellow Magic Orchestra, Vangelis, Jarre and Prince. 

And available to gaze at on a glorious mug!