Roland Jupiter-8

Features and architecture

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 or clock input via CV jacks on the rear panel. An assignable bender can 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, it 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.

A Zilog Z80 CPU managed storage of patches, scanning the keyboard and front-panel controls, displaying patch numbers, and handling the auto-tune function. The VCF was based on the custom Roland IR3109 IC, the VCA was the BA662, and the envelopes were generated in hardware by the Roland IR3R01 chip, offering much faster attack (1 ms) than the software-generated envelopes used in later models.

In the present day

The wide range of sounds the Jupiter-8 can produce, its efficient front panel layout with dedicated controllers for each parameter, and its sturdy construction make it a desirable instrument even 35 years after first production. Units in good condition still fetch significantly more at auction than most new synthesizers. For example, Alicia Keys can be seen playing one in the video for her number one hit "No One" from September 2007.

Jupiter changes and successors

Throughout production of the JP-8 there were several changes. Starting at serial #171700 the D/A converter on the Interface board was changed from 12-bit to 14-bit, mainly to improve tuning stability; the 12-bit converter could cause the autotune to be inaccurate in some instances. Some advise avoiding early JP-8s while others report no tuning problems. Starting at serial #242750 the LEDs of the display were changed to brighter ones.

Starting at serial #282880 the JP-8 came standard with a DCB port; these newer units may be referred to as JP-8As. DCB was Roland's pre-MIDI interface allowing communication with other DCB-enabled hardware such as the MC-4 and MC-8 microcomposers; earlier JP-8s could have the OC-8 retrofit installed for DCB capability. The Jupiter-6, released two years after the JP-8, was a more affordable version with six voices and a similar appearance. It used integrated circuits (Curtis CEM3340 for oscillators and CEM3360 for VCAs) rather than discrete circuits, giving it a distinct sonic character.

The Jupiter-6 features a true multimode resonant filter, built-in MIDI, unison detune function, and the ability to activate multiple waveforms on a single oscillator. The MKS-80 Super Jupiter is a MIDI-controlled rack-mountable sound module with similar voice architecture; its first incarnation (revision 3 and 4) used hardware similar to the Jupiter-6, while the 1985 Rev 5 used different VCO, VCA and filter circuits, sounding somewhat different.

Notable users

Notable users of the Roland Jupiter-8 include ABBA, Damon Albarn, BT, Jonathan Cain of Journey (most notably on "Separate Ways"), Vince Clarke, Duran Duran ("Hungry Like the Wolf", "Save A Prayer"), Marvin Gaye (the Jupiter-8 and TR-808 were primary tools on his 1982 album Midnight Love), Ilaiyaraaja (Punnagai Mannan), Michael Jackson (Thriller), Nero, Howard Jones, Giorgio Moroder, Orchestral Manoeuvres in the Dark (Junk Culture), Pet Shop Boys (Behaviour), Queen (albums Hot Space, The Works, and A Kind of Magic), Andy Richards (song "Relax" by Frankie Goes to Hollywood), Charanjit Singh (Synthesizing: Ten Ragas to a Disco Beat), Sparks (keyboardist Ron Mael rearranged the letters on the front-facing Roland logo to read "Ronald"), Tangerine Dream (Poland), Tears for Fears, and Ultravox.

Did You Know?

• The soldered-in battery typically lasts ten years or more, ranking these boards among the lowest-maintenance of their generation.
• A Jupiter-8 plug-out was included already installed on the Roland System-8 synthesizer in 2017.