Roland JX-10 (1986–1989)

Name: Roland JX-10
Brand: Roland

Two JX-8Ps bolted into one 76-key chassis, and the last real-analog poly keyboard Roland ever built.

The JX-10 was announced in the UK press as a dual-voice polyphonic synthesiser, and reviewers noted that its pressure-sensitive keyboard made it well suited as a master controller (Studio Sound, September 1986, p.32).

Overview

Roland took the JX-8P and doubled everything. Twenty-four DCOs. Twelve voices. Seventy-six keys. The chassis is wide enough that you should think about where it's going before you buy it. Roland's own marketing billed it as two JX-8Ps in one instrument, and the service documentation backs that up - the module boards are split into UPPER and LOWER sections, each handling its own set of voices through its own VCO, VCF, and VCA chain. A single assigner CPU runs the show, with two module CPUs and a display CPU doing the grunt work underneath. It's a processor-controlled polyphonic analogue synthesizer in the most literal sense: analogue voice architecture, digital control over every parameter.

Seventy-six keys with velocity and aftertouch make the JX-10 a natural master controller for a rig. The 1986 UK press picked up on that - a contemporary report noted the pressure-sensitive keyboard made the JX-10 well suited as a MIDI master controller (Studio Sound, September 1986, p.32). That's a period observation, not a marketing line. If you're running a studio with a rack of expanders, this is the board you play them from.

Patch memory runs to 64 programs, each one a combination of sound and performance control functions. The manual is specific about this - the JX-10 stores programs, not just patches, so splits and layers come back the way you left them. The effects section is minimal: a chorus with three settings (off, slow, fast) and a chase-play delay function that alternates patches between the upper and lower modules to create programmable delayed repeats. You won't find that feature on many other synths, and it's one of the reasons the JX-10 has a small but devoted following.

There's a persistent argument about whether the JX-10 really sounds like two JX-8Ps. Some owners dispute Roland's marketing claim, prefer the JX-8P's tone and point to hardware differences between the two. The filter control code is reportedly identical between the JX-8 and the JX-10 - that comes from a conversation with Fred Vecoven, the engineer behind the JX-10 v3 firmware - but identical code doesn't guarantee identical output. The "Super JX" name that appears on the MKS-70 and JX-10 alike was Roland's own shorthand, and like most marketing shorthand, it's approximately true rather than precisely true.

Key Features

Dual-Engine Architecture: 24 DCOs Across Two Modules

The JX-10's voicing splits into UPPER and LOWER module boards, each with its own set of DCOs, filters, and amplifiers. This isn't a single engine with a split point - it's two complete signal paths running in parallel. Dual and split modes feel different from a single-engine synth doing the same thing, because the two halves have their own independent voice allocation. The 12-voice polyphony is the headline number, though one source claims a maximum of only 6 voices. That's almost certainly a misunderstanding of how the dual-module architecture allocates voices, and the 12-voice figure appears consistently across multiple sources. The JX-10 is a 12-voice instrument.

76 Keys with Velocity and Aftertouch

Seventy-six keys is an unusual count - more than the standard 61, fewer than a full 88. The aftertouch is the JX-10's most notorious failure point. When it works, it's expressive and musical. When it doesn't - and it often doesn't after thirty-plus years - it becomes an on/off switch that can't produce a varying signal proportional to pressure. More on that in the collectibility section.

Chorus and Chase-Play Delay

The onboard effects are minimal by modern standards. The chorus has three states: off, slow, and fast. No depth control, no rate knob. The chase-play delay is more interesting. It creates delayed repeats by alternating patches between the upper and lower modules, so the delay isn't a separate effect processor but a product of the dual-engine architecture. The repeats can be programmed, and you can't replicate the effect with a standard delay pedal.

64-Program Patch Memory

Sixty-four programs, each storing a combination of sound and performance control functions. That's not a lot by modern standards, but it covers a live set if you're disciplined about it. The memory is battery-backed, and the service manual includes a lithium battery warning in four Scandinavian languages.

Historical Context

The JX-10 was manufactured from 1986 to 1989, and it was on the market by September 1986. Roland placed advertisements in International Musician in November 1986 and in Sound On Sound in February 1987, which gives a clear picture of the launch window. One source describes it as an early-1980s instrument, but the production dates and the advertising record contradict that. The JX-10 is a mid-to-late-'80s machine.

It arrived at the end of Roland's analogue era. The JX-3P had come out in 1983, and by the time the JX-10 was shipping, analogue polysynths were on their way out. The JX-10 was Roland's last real-analog polyphonic synthesizer keyboard - the MKS-70 rack version shares the "Super JX" name and much of the architecture, but the keyboard version was the end of the line. Collectors sometimes describe it as the unsung hero of the Roland armada.

Collectibility & Value

The JX-10 has a loyal following but hasn't reached the price heights of the Jupiter-8 or even the Juno-106. UK classified listings from the late 1990s show a "Super JX10" in good condition at £280 in 1997 (Sound On Sound, June 1997, p.259), a JX10 at £485 in 1996 (Sound On Sound, November 1996, p.261), and a JX-10 paired with the PG-300 programmer at £799 in 1998 (Sound On Sound, March 1998, p.70). The "Super JX10" name seems to have been used interchangeably with "JX-10" in the second-hand market, so don't be confused if you see both. The PG-300 was the companion programmer for this instrument, and the PG-800 - originally designed for the JX-8P - also appears in JX-10 listings, suggesting some cross-compatibility or at least cross-listing confusion.

Two failure points dominate ownership. The first is aftertouch. A pristine JX-10 with dead aftertouch is a common story - one owner reported attempting several repairs before giving up, with the sensor either working as an on/off switch or not at all. Replacement aftertouch sensors have been produced by third parties, and the original AT-JX-10 was reportedly expensive to manufacture and ship. The second is the display. The far-right character position going intermittent is a known issue, and replacement displays are available from specialist suppliers.

Other parts are obtainable. Slide potentiometers - 30mm travel, 15mm lever, original Panasonic - turn up for sale, as do rubber key bushings in sets of six. Fred Vecoven has been migrating his JX-10 v3 firmware for use in the JX-8P. If you're buying one, test the aftertouch thoroughly and check every character position on the display. Neither problem is cheap to fix if you have to source parts yourself.