The Jupiter-8 is an 8-voice polyphonic analog synthesizer. Each voice features two discrete VCOs with cross-modulation and sync, pulse-width modulation, a non-resonant high-pass filter, a resonant Low-pass filter with 2-pole (12 dB/octave) and 4-pole (24 dB/octave) settings, an LFO with variable waveforms and routings, and two envelope generators (one invertible).

Features include adjustable polyphonic portamento and a hold function for infinite sustain of notes and arpeggios. A versatile arpeggiator can be synchronized with external equipment by using the proprietary Roland DCB interface, clock input via CV jacks on the rear panel. An assignable bender can be used to control pitch or filter frequency.

The Jupiter-8 includes balanced XLR outputs as well as unbalanced 1/4" outputs for the ”Upper” and ”Lower” presets in Split mode. In addition to monophonic and polyphonic modes, the Jupiter-8 includes a unique polyphonic unison mode, in which all 16 oscillators can be stacked onto one note, but divide down if more keys are pressed. No other polyphonic synthesizer at the time had this feature.

Synth is in excellent condition and has recently been serviced. The Jupiter-8 also has a midi modification that works great.