Roland's latest polysynth combines the hardware of two JX8P's, but adds many new features which are unavailable elsewhere. Does it stand up as a complete instrument in its own right?

With the ever-broadening range of synthesis options available to keyboard players nowadays, it's all too easy for instruments to end up discarded before their time. However, Roland's latest synth, the 12-voice JX10, shows a refreshing faith in familiar technology - more specifically the voice architecture of the company's popular JX8P (reviewed in E&MM February '85). In sonic terms it's two JX8Ps combined, with Split and Dual performance modes and a whole host of programmable internal and MIDI performance features. To this already impressive spec, Roland have added an onboard real-time sequencer and the enigmatically-named 'Chase Play', of which more anon.

Appropriately enough for its price tag, the JX10 has been given a 76-note keyboard with attack velocity and channel aftertouch sensitivity. These dual dynamic attributes were still rare when we reviewed the JX8P, but nowadays are pretty de rigueur on any upmarket synth. Release velocity and polyphonic aftertouch are still all too rare, however, and Roland haven't seen fit to include them on their latest. But importantly, the 10's shallow-travel keyboard is pleasing and responsive to the touch, firm and yet agile.

The new Roland's front panel includes one of the most intelligible and informative displays to be found on a synth in the form of a 32-figure fluorescent LED affair, and the well-organised front panel strikes a good balance between accessibility (complete with many dedicated buttons) and economy. The company's much-vaunted 'alpha dial', which is used for altering parameters and values, still fails to convince, however - in practice it's an awkward device with neither the immediacy or flexibility of the familiar combination of slider and +/- buttons. In contrast, the 10's numeric keypad offers very quick access.

For the posers of this world the Roland's sleek appearance and black-and-grey finish really look the business. More importantly, the JX is a solidly-constructed instrument which should be able to take a few knocks - though watch those overhanging keys.

Roland have given their latest JX the ability to access 100 sounds internally (50 of which are preset on ROM) and a further 50 on M64C RAM cartridge. That's a healthy number, easily expandable with further cartridges - though at £85 per cartridge you'd be better off storing sounds to computer via MIDI, keeping your cartridge(s) for your live set.

The ability of a synth to organise its sounds and to communicate with other instruments in musically meaningful ways is increasingly important, and this is an area in which the JX10 leaps ahead of its predecessor. For the new JX includes 64 Patch memories onboard and a further 64 on cartridge along with the sounds. These Patches (Roland call individual sounds Tones, just to confuse things) can call up two sounds onto the keyboard and define how these will be used: ie. in Whole (with either the Upper or Lower sound), Split or Dual modes. Front-panel selectors allow you to instantly switch from one mode to another, which can effectively give you many more sonic combinations than the 10's storage capacity would seem to allow.

The JX's Patches allow you to define a healthy number of features. Transposition (over a ± two-octave range), detune, hold on/off, LFO modulation depth, portamento on/off and pitch-bend on/off can each be set individually for Upper and Lower sounds in each Patch. It's also possible to set the effect that aftertouch will have on vibrato, brilliance and volume for both sounds in a Patch, together with a total volume level, Upper and Lower splitpoints (which can be overlapped), portamento time and pitch-bend range. And in addition to the standard dual voicing mode you can choose to crossfade between the two sounds (using aftertouch) or select between one or the other sound depending on the velocity with which you strike the keys; in the latter instance you can even decide where the changeover point will be on the basis of the splitpoint value (which is of course otherwise inoperative in dual mode).

Six Patch-programmable key assign modes (independently programmable for Upper and Lower sections) allow you to decide how the JX's voices will be assigned to the keyboard. Two poly modes allow for either normal performance, with each voice playing through its allotted release time, or a style in which each new note clips the release time of the current note. Unison assigns two voices to a key, making each keyboard section three-voice polyphonic; one mode plays each voice at the same pitch, the other sets them an octave apart. Mono modes turn each of the Upper and Lower keyboard sections into monophonic synths, with either a single voice or all six voices stacked up on a single note - great for those blistering solos.

Further adding to the performance flexibility of the JX10 are two assignable continuous controllers which may be activated either from dedicated front-panel sliders or footpedal inputs, together with an assignable footswitch controller. The continuous controllers can be assigned to either Upper/Lower volume balance, portamento time, total volume, Upper MIDI volume or Lower MIDI volume. As its name implies, total volume governs the JX10's volume and that of other MIDI instruments (making it useful as a master fade control), while MIDI volume by itself is a handy way of balancing the volume of slave instruments against that of the JX in real time.

The footswitch controller can be assigned to step sequentially through the JX's Patches or turn portamento, chase play, Upper hold or Lower hold on/off.

Unusually, Roland have given the JX10 separate stereo outs for Upper and Lower sounds, along with a stereo mix output, mono outs and a single 'total mix' - a comprehensive selection which should satisfy a variety of requirements.

"Facilities: Where Chase Play differs from a standard DDL is that you can use two different sounds to create otherwise unobtainable effects."

The JX's voice architecture has the virtue of familiarity if not of originality - and that's no bad thing in this case. There are two DCOs per voice, two ADSR envelope generators, an Oscillator Mixer, LFO, VCF and VCA, together with the familiar Roland chorus (offering a choice of 'rich' and 'expansive' settings!).

Each DCO offers a choice of four 'traditional' waveforms (sawtooth, square, noise and pulse) and may be tuned over four octaves. Pitch can be modulated by either the LFO (which offers sine, square or random waveforms) or the envelopes (which can be set positively or negatively) and the two oscillators can be cross-modulated. You can mix the levels of the two DCOs, and control DCO2's level from keyboard velocity - which allows you to introduce specific effects or significantly alter the timbre of a sound from the strength of your touch on the keys.

Even though the front panel Edit Map lists all the Tone parameters for ready reference, there's no denying that calling up parameters one by one into the central display can become a trifle laborious. Fortunately, Roland have for some while been producing sleek little boxes with knobs and sliders on them. These plug into a certain number of the company's synths and give you all the accessibility, speed of operation and ease of comprehension you've come to expect from an analogue as opposed to a digital front panel. Not surprisingly the JX10 can use the PG800 programmer that was originally designed for the JX8P. You do have to fork out extra pennies for the privilege, but the PG800 is worth its weight in gold...

The JX10 offers plenty of those warm 'analogue' sounds for which Roland are justly famous (though the 10 is actually an analogue/digital hybrid), and a number of the best sounds from the JX8P are to be found on the new instrument. And while 50 presets (half of the internal memory) might seem a slightly high proportion, Roland have made sure that these include a fair cross-section of sounds, and more importantly that many of the sounds are classic Roland which you'll probably want to keep and use frequently. Thus there are plenty of those warm electric pianos and silky strings (the latter including the sublime 'Soundtrack' from the JX8P), together with some punchy synth bass sounds, wonderfully delicate oriental-style percussion voicings, a very ethereal pipe organ and some abrasive brass sounds.

The programmable sounds are a less consistent bunch, but in part this seems to be because Roland have included sounds which work most effectively when combined with another sound in Dual mode. Roland have chosen to construct dual voicings for almost all their factory-programmed Patches, which has paid off in showing the instrument to good advantage.

The Patch and programmable Tone memories can be transferred between synth and M64C cartridge in one go (and similarly sent and received over MIDI), but you can also transfer individual Patches and individual Tones to any memory positions you want.

The inclusion of an onboard sequencer (single track, real-time only) may seem superfluous given the current proliferation of dedicated and computer-based sequencers, yet its accessibility and simple operation make it a useful feature to have around.

There are only two parameters: sequence repeat on/off and sequence tempo. And of course, once you've recorded your sequence you're free to play over it using the remaining JX voices; what's a pity is that you can't assign the sequence to one sound in Dual mode and play over it with the other sound.

It's worth noting that the 10 has no onboard sequence memory; in order to record anything you need either Roland's M16C or M64C cartridge. These can record approximately 400 and 1600 notes respectively, but they're not exactly the cheapest form of sequence storage - all the more reason to commit your lasting musical thoughts to an external sequencer, using the internal sequencer for trying out ideas.

"Specification: In addition to the standard dual voicing mode, you can choose to cross-fade between the two sounds using aftertouch..."

The Chase Play feature turns out to be none other than our friend of recent Korg acquaintance, the built-in DDL. Well, almost. The new JX doesn't achieve its delay effects by processing an audio signal; instead, there's some clever real-time manipulation of the synth's voices to give DDL-type effects. This approach does mean that you're tied to the JX's voice limit, but for many uses that's not too much of a problem.

Chase Play works in Dual mode only, sounding the Upper tone as you play a note and delaying the Lower tone. Three modes allow you to choose between a one-off Upper/Lower delay for each note played, Upper followed repeatedly by Lower, or alternation between Upper and Lower. Where this differs from a standard DDL is that you can use two different sounds (perhaps at different transpositions) to create otherwise unobtainable effects.

Two further parameters govern delay time (up to four seconds, variable over 100 steps) and delay level, the latter governing the number of repeats for each note played - with the maximum being just over 100. Hey presto, you've got a sequenced drone pattern from playing one note. In practice Chase Play is an extremely versatile feature, made all the more useful by being Patch-programmable.

Roland have long been one of the most thorough manufacturers when it comes to putting MIDI on their instruments, and the JX10 is no exception. MIDI parameters that are Patch-programmable allow Upper and Lower sections to each be given their own MIDI transmit channel (which needn't be the same as the receive channel) or set to no transmit, and to each send their own program change number (1-128) and MIDI volume level when a patch is selected - the last-mentioned can help to balance sounds on master and slave instruments. It's also possible to set a MIDI channel transmit splitpoint independently from the JX's own splitpoint(s), allowing for greater flexibility in creating sound textures.

A useful (and original) feature of the JX10 is the ability to assign a separate channel for Patch program changes as opposed to Tone program changes. Thus you can change Upper and Lower Tone memories independently of Patch memories, enabling you to associate several Tones with each Patch. MIDI parameters that can be set on or off independently for Upper and Lower sections (but not for each Patch, unfortunately) are program change, aftertouch, pitch-bend, modulation, portamento, hold, volume and local. What's also a pity is that there's no option to control the two JX sounds independently (from a sequencer, say) when in Dual mode.

Time for conclusions, and they're not difficult to reach. The JX10 is a professional instrument of the first order which proudly joins the ranks of the megasynths. If you're looking for a master instrument, it's a role that the 10 fulfils admirably.

There are, of course, other worthwhile instruments vying for your attention which occupy the same price bracket as the 10. Known quantities are Yamaha's DX5 (with a recently reduced price tag) and Oberheim's Matrix 6, whilst as yet still something of an unknown quantity is Sequential's Prophet VS.

In these innovation-conscious (some would say novelty-conscious) times, it is tempting to ignore anything that doesn't offer the very latest in technological prowess. The JX10 is certainly familiar territory both sonically and in its range of programming possibilities, yet that needn't be a shortcoming. The latest JX makes damn good sounds, and in other respects it offers as much if not more than many other synths currently on the market. It's an extremely well-thought-out and flexible instrument that's above all responsive to musical needs both in the sounds that it makes and in the way that it allows you to organise those sounds internally and in conjunction with other MIDI instruments. Ignore it at your peril.