This is a classic synthesizer in big demand now. Ours is MIDI retrofitted and modified with a ring modulator and 4 banks of memory for flexibility and sound variation. A fabulous piece of vintage gear.
From Wikipedia – http://en.wikipedia.org/wiki/Roland_Jupiter-8
The Jupiter-8 is an eight-voice polyphonic analog subtractive synthesizer introduced by Roland Corporation in 1981. The Jupiter-8, or JP-8, was Roland’s flagship synthesizer for the first half of the 1980’s. Although it lacked the soon-to-be standard of MIDI control, later model Jupiter-8s did include Roland’s proprietary DCB interface, and all of them sported advanced features such as “Four on Four” and the ability to split the keyboard into two zones, with a separate patch active on each zone.
Features & Architecture
The Jupiter-8 is an 8-voice polyphonic analog synthesizer. Each voice features two 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, or one of the aftermarket MIDI kits from Encore or Kenton. An assignable bender can be used to control pitch or filter frequency.
From the factory, the JP-8 could store 64 patches. Patches could be stored to, or loaded from, a standard analog tape/cassette. The Encore JP8MK MIDI kit doubles the patch memory to 128  and enables the JP-8 to store and recall patches over a MIDI connection, using a computer with sysex utility software.
The Jupiter-8 incudes balanced stereo XLR outputs as well as unbalanced 1/4″ outputs. In addition to monophonic and polyphonic modes, the Jupiter-8 includes a unison mode, in which all 16 oscillators can be stacked into a single monophonic patch.
A Zilog Z80 CPU was used for managing storage of patches; scanning the keyboard and front-panel controls for changes; displaying the current patch number and other information on the display; and taking care of the auto-tune function, among other things. The VCOs were discrete. The VCF was based on the custom Roland IR3109 IC (also used in the filter circuits of the Jupiter-6, later Jupiter-4 units, MKS-80 rev 4, Juno-6/Juno-60, SH-101, MC-202, JX-3P and packaged in the 80017a chip used in the Juno-106 and MKS-30 among others). The VCA was the BA662, used also in Juno-6/60/106, JX-3P and TB-303. The envelopes were generated in hardware by the Roland IR3R01 chip (also in the Juno 6/60), and are much faster (1ms attack) than the software-generated envelopes used in the later Jupiter-6, Juno-106 and MKS-80 “Super Jupiter”.
There are claims that early models had unstable tuning, mainly due to their panel slider encoding resolution and main control voltage generation. However, this may be limited to the first 500 JP-8s that were manufactured . Beginning with serial number 171700, the 12-bit DAC was upgraded to a 14-bit DAC. This increased the resolution of the controls but had little to no effect on the overall sound quality. The soldered-in battery typically lasts ten years or more, ranking these boards among the lowest-maintenance of their generation.
In The Present Day
The wide range of sounds that the Jupiter-8 can produce, the efficient front panel layout (each synthesizer sound parameter adjustment had its own dedicated controller), and its sturdy construction, make the Jupiter-8 a venerable and desirable instrument even 30 years after it was first produced. Units in good condition still fetch more at auction than most new synthesizers, suggesting that the Jupiter-8 will continue to be heard for years to come. While the characteristic sound of the Jupiter-8 can be heard on many songs from the early 1980s onward, its still being recorded to this day. For example, Alicia Keys can be seen playing one in the video for the number one hit “No One.”
From Vintage Synth Explorer
The Jupiter 8 was Roland’s first truly professional analog synthesizer. The Jupiter 8 features 16 rich analog oscillators at 2 per voice, eight voice polyphony and easy programming! At eight voices you can get some pretty thick analog sounds. Easy and intuitive programming via front panel sliders, knobs and buttons for all your tweaking needs. The legacy of the Jupiter synthesizers is due to their unique voice architecture and design, creating sounds that were so unreal and amazing that they have to be heard! No other synths in the world can create analog sounds as cool and authentic as these.
The Jupiter 8 was the biggest and fattest of them all (Jupiters and Junos)! It was one of the first synths to allow its keyboard to be split and layered – it’s eight voices of trance heaven! Cross-mod, oscillator sync, a great LFO and a classic arpeggiator are also on-board. (The arpeggiator can be heard all over the Duran Duran classic, “Rio”.) There’s also two killer resonant analog 24dB/oct filters with 2-pole and 4-pole settings as well as low- and high-pass filtering methods. Unfortunately for the earlier models, tuning was very unstable but that seemed to be resolved in later models. Unlike its smaller counterpart, the Jupiter 6, the Jup 8 does not feature MIDI, only Roland’s DCB sync can be found on some models. However, MIDI retro-kit’s are available from various companies. Patch presets can store keyboard splits, arpeggiator settings, voice assign mode, hold, portamento and modulation settings.
The Jupiter 8 has been used by Tangerine Dream, Orbital, Future Sound of London, Moby, Duran Duran, Underworld, Vince Clarke, Uberzone, Jean Michel Jarre, Roxy Music, OMD, A Flock Of Seagulls, Depeche Mode, Rush, Meat Beat Manifesto, Banco De Gaia, Josh Wink, Thomas Dolby, Howard Jones, The Cars, Prince, Gary Wright, Jan Hammer, BT, Adrian Lee, Heaven 17, Kitaro, Elvis Costello, Tears for Fears, Huey Lewis and the News, Journey, Moog Cookbook, Toto, Yes, Devo, Freddy Fresh, George Duke, Greg Phillanganes, Jonathan Cain of Journey, Greg Johnson & Kevin Kendrick of Cameo, Stevie Wonder and Simple Minds.
From Sound on Sound
Three years on, the world was still awash with American synths. Sequential Circuits had remained the market leader, with Oberheim running a close second. As for the Japanese… well, everybody ‘knew’ that they couldn’t make real polyphonic synthesizers. The Korg PS series (which had eventually included three models, the PS3100, PS3200 and PS3300) were commercial flops, and the cheaper PolySix lacked the kudos to be taken seriously. It was into these hostile waters that Roland launched an 8-voice Jupiter, the JP8. Unfortunately, it made very little impact. A few bands adopted it, but only to supplement their American synths, not to replace them.
Yet right from the start there was something a bit special about the Jupiter 8. Prophets and Oberheims were always heavy-sounding, thick and imposing. In contrast, the Jupe seemed capable of much greater clarity and transparency. Unlike any other synth of its era, it didn’t impose its own character upon a sound: if you wanted ‘fat’, you could have it; If you wanted ethereal, you could have that too. Indeed, the Jupiter 8 sounded as it looked — beautifully sleek and polished — in exactly the way that the American synths didn’t. Why this should have been so is one of life’s little mysteries. After all, they all shared two VCOs per voice, a 24dB/octave low-pass filter, a pair of traditional ADSR envelope generators, and a wide range of modulation options. But there it was: Prophets were fat, imposing, and dominated a mix, whereas the Jupiter 8 would happily complement other sounds without overpowering them.
Furthermore, the Jupiter 8 bristled with features its competitors lacked. It had a split keyboard and numerous keyboard assignments, so that you could, for example, play unison lead lines above left-hand pads, or electric pianos above grunting basslines. It offered oscillator sync, cross modulation, switchable 12dB/oct and 24dB/oct filtering, and polyphonic portamento. It saved and loaded voices reliably via its cassette interface, and it incorporated a superb arpeggiator that featured what is still my favourite Jupiter facility — ‘random’ mode. This added instant ‘sparkle’ to almost any track. Finally, there was a comprehensive complement of analogue interfaces that controlled the arpeggio speed, portamento, sustain, filter cutoff, and the VCA. Add the CV and Gate outputs (with the pitch CV derived from the highest note played), and the result was an impressive package of features.
Released in 1982, a full year before the appearance of MIDI, an upgraded Jupiter 8, the JP8A, offered a number of improvements, with greater tuning stability, and an updated LED screen. It was also the first synth to take a credible stab at talking to another instrument polyphonically. The interface that made this possible was called DCB, and it almost certainly was the most important factor in ensuring the synth’s success. The early 1980s were the heyday of electro-pop, and, long before the arrival of MIDI and the Atari ST, bands were writing songs based upon short programmed musical sequences. The machines they used for this were Roland’s MC4 and MC8 Microcomposers. DCB allowed the Jupiter to communicate with each of these, as well as with the Juno 60 and a range of ‘JSQ’ sequencers. Suddenly polyphonic sequencing was an affordable reality. The pop community was convinced: ‘Relax’, by Frankie Goes to Hollywood, was dominated by a Jupiter 8, Nick Rhodes relied heavily upon his 4s and 8s, and players such as Steve Luscombe (Blancmange), Vince Clarke (Erasure), John Foxx, and Martyn Ware (Heaven 17) were soon adopting the JP8. Roland even took care of owners of the original model by releasing a DCB add-on board, the OC8, that could be retrofitted to early Jupiter 8s. Indeed, another Roland box, the MD8, eventually made it possible for DCB to talk to MIDI, so the Jupiter 8 became one of the first big analogue synths with MIDI, years before retrofits became available for many of its contemporaries.
|Oscillator:||2 VCOs per voice|
|Synthesis type:||Analog subtractive|
|Filter:||12 or 24 dB/octave resonant lowpass, non-resonant highpass|
The Jupiter 8 and 8A had one other quality that made them more desirable than their competitors. Due to slack manufacturing and electrical tolerances, voices programmed on one example of a Prophet or Oberheim could sound quite different on another, ostensibly identical, one. Some players have called that defect ‘individuality’, but I don’t imagine they were very happy when they walked into a studio costing £100 per hour, loaded their patches into the studio synth, and found that all their string ensembles had become composite brass patches. This never happened on a Jupiter 8 or 8A (otherwise I wouldn’t have mentioned it).
This is IMHO the ultimate analog machine. The possibilities are vast and by tweaking them good ole knobs and sliders while playing, it’s easy to make nice things happen. My favourite is the “solo” mode which stacks all 16 oscillators on a single key depression, creating an incredibly thick and beefy sound.
On the sad side, there is no MIDI (this is an oldie, remember?), although you can use a DCB to MIDI interface (if you can find one).
Thomas R Kolb
This damn board has absolutely impressive analog sounds! Altough it has no modular capabilities or complex modulation routings, what it does, it does so darn well! It’s even fatter than the Jupiter-6, I think due to its oscillator structure. The JP-6 uses Curtis Electromusic chips for oscillators, and the JP-8 employs oscillator boards, with discrete components. It features one LFO with sine, saw, square and random waveforms, VCO-1 with triangle, saw, variable pulse or rectangular waveforms, and VCO-2 with sine, saw, variable pulse or pink noise waveforms. The VCO-2 is syncable to VCO-1.It features a mixer knob, to balance between VCO-1 and VCO-2. It has a non-voltage controlled high-pass filter, and a voltage controlled low-pass filter with selectable cutoff slope of -24dB/oct or -12db/oct; the resonance does not cranks to self-oscillation. the VCF can be modulated from the env-1 or env-2 and LFO. The VCA can be modulated by env-2 and LFO. It has two envelope generators, with key follow. Its envelopes uses analog ADSR chips, the IR3R01, which provides 1msec attack time, very suitable for punchy attack synth basses. The JP-8 features an arpeggiator, with four octave range, with up/down/up&down and random modes. It can be set in “whole” mode, with one single patch across the keyboard and 8-voice polyphony, “split”, with a four-voice different patch in each side of the keyboard, and “dual”, with two different patches layered together providing 4-voice polyphony. It has also a CV/gate output. Altough most pictures found on the net shows the JP-8 as a black keyboard, it has a metallic charcoal grey finishing, just like the JP-6. I love its rugged Jeep-like construction, with thick aluminium side panels.