1996 Korg Prophecy Solo Synth

Bob Leggitt | Monday, 5 December 2011
Korg Prophecy arty pic with buttons glowing in the dark

By the early 1990s, the trend in synthesis was firmly anchored in sample-based tone production. A large collection of real instrument multisamples would be recorded and assembled in the synth’s memory, then a series of digital subtractive parameters would be employed to tailor the basic multisample to taste. Programmers would produce a set of factory presets, the synth would ship, and more often than not, the owner would use the instrument as a simple preset bank.

There was no real scope for editing the sounds on-the-fly during performance. Since the Yamaha DX7 proved that a mid ‘80s synth didn’t need a ‘dashboard’ of rotary knobs, no one had significantly contradicted the idea of a ‘clean’ front panel. For a good decade, editing sounds had been a cold, calculated data entry process, conducted well away from the public gaze. Indeed, a high proportion of keyboardists didn’t edit or program at all. They used the synth as is, and if they wanted a change, they either waited for a third party to create a new sound bank, or they bought a new synth.

But since the late ‘80s, as the novelty of digital synthesis started to wear thin, interest had been returning to analogue gear. As time progressed through the early ‘90s, more and more electronic music employed supposedly obsolete analogue technology to create ‘movement’ within a keyboard line. Rotary knobs on the instrument’s ‘dashboard’ would be used to morph the sound during performance, lending interest to an otherwise repetitive sequence.

By 1994, this was something makers of new equipment could no longer ignore. It wouldn’t have been a particularly competitive move to go back to making actual analogue synths, but there was a technology, employed in Yamaha’s new VL1 synth, which could digitally power the type of instrument fans of contemporary electronic music were looking for.

The Yamaha VL1 was produced with the aim of digitally replicating acoustic instruments, and certainly wasn’t of great interest to the dance music genre. But rather than using samples to create its sounds, it employed a new concept called physical modelling. With physical modelling, the parameters changed according to the type of instrument to be simulated. All the sounds were generated using mathematical calculations, but whereas with the FM synthesis of the ’80s a brass sound would be made the same way as a piano sound, physical modelling related each parameter to a physical component of a real instrument. So, for example, a physically modelled bass guitar would not have generic adjusments for ‘operator modulation’ or ‘filter resonance’, but instrument-specific adjustments for ‘pluck noise’, ‘string position’, etc.

1996 Korg Prophecy Solo Synthesizer

Introduced in 1995, the Prophecy solo synth was a flash of pure genius from Korg, in numerous respects. The first and most obvious triumph was the decision to use the new physical modelling principle to digitally replicate analogue synthesis, and then link in with that an array of real time control knobs and gadgets. But as a physical modelling synth, the Prophecy wasn’t limited to virtual analogue usage – it also had physical models for brass instruments, reed instruments and plucked string instruments. Added to that was a Variable Phase Modulation mode (essentially the Korg take on Frequency Modulation – FM), plus Comb Filter and Ring Mod oscillators. Seven separate synthesis types in one highly compact keyboard. Korg's own term for physical modelling was MOSS - standing for Multi Oscillator Synthesis System.

It could be said that there was a major downside to the Prophecy – this being that it was not only monophonic, but also monotimbral. It could only produce one note at a time, full stop. It was a very long time since synth manufacturers had been constrained to such spartan territory, but in this early phase in the development of physical modelling, monophonic output was all that was commercially feasible. Yamaha had displayed considerable guts to release their monophonic VL1 – especially given its asking price of nearly four grand – so a great deal of credit is due to them for testing the water. But frankly, any manufacturer going back to monophonic/monotimbral confinement in an environment where other synth models could play an entire 16-track arrangement, was taking a risk.

Rather than trying to play down the Prophecy’s limitation, however, Korg in fact played right up to it, and that was a very clever piece of thinking. The short keyboard and the designation of ‘Solo Synthesizer’ put keyboardists in mind of vintage classics such as the Minimoog, not to mention Korg’s own ‘70s marvel the MS-20. A series of real time control knobs on the front panel combined with a versatile log and ribbon controller to restore the feel of a ‘dashboard’, and no one with any knowledge of dance music creation was left in any doubt that the Prophecy was a modern take on the analogue monosynth. Everything about the design was impressive. The individual yet attractive looks, augmented by an evocative model name rather than the typical series of numbers and/or letters, probably sold a fair number of units in itself. The presets were cool, the keyboard had a nice feel (as well as aftertouch) and joy of joys, there was a truly wicked arpeggiator on board. I used the Prophecy and its arpeggiator heavily in the recording of the track on the audio stream below...

[UPDATE: The example sound stream was hosted on Tindeck. Since Tindeck closed in 2018, the stream is now inoperable..]

You don’t really get the full impact of a Prophecy until you use one. It was very tempting in 1995 to say: “Yeah, yeah, monophonic synth, costs over a grand, I’ll get back to you on that one mate.”

But as soon as you called up a nice phat analogue preset, engaged the arpeggiator on latch, dropped a chord shape and then started to play with the gadgets, you were hooked. The built-in digital delay would blend the repeats of one note with the initial sounding of the next as the arpeggio pumped away. So whilst the Proph couldn’t technically play chords, it could produce them courtesy of the powerful delay unit. Then as you twiddled around with the filter settings (user-assignable to various different knobs on the front panel) you really started to hear something sonically inspiring. A morphing, squelching groove with that thunderous bottom-end you’d typically associate with ‘70s analogues. Sync the Prophecy to a drum machine with something like a TR-808 or TR-909 kit loaded, and all you needed was a set of lyrics. You actually felt guilty creating such awesome grooves whilst doing so little work, and having so much fun!

The biggest drawback for those who were naturally drawn towards an instrument like the Prophecy was that once you decided you wanted to make edits beyond the scope of the front panel knobs and gadgets, you were back in the gruelling, push-button territory of numerical data entry. I find the Prophecy a pain to program beyond just tweaking presets on the front panel, and I speak as someone who once programmed an entire DX7 internal memory from scratch, so I’m not normally put off tinkering about ‘under the bonnet’.

The brass and reed models were something I imagine the typical user could have done without, and whilst they were more expressive than sample-based creations, there was something about them which said they were synthesized rather than real. I personally didn’t persevere much with them. The electric/acoustic bass model I found much more useful, and in fact I still use an edit of the factory preset Rock Bass a great deal. It does sound very convincing to me, I love the way it responds to key velocity, and it’s much more convenient than setting up to record real bass guitar. But I don’t see these models, or even the VPM, as having any great bearing on the success of the Prophecy. It works best and is most exciting when used as a virtual analogue monosynth. That was its market, and that’s what really shifted the stock.

Ultimately, £1,000+ was a lot of money to be paying for a monophonic/monotimbral keyboard in 1995, and despite how much I loved the Prophecy I held off buying one until late 1996 when prices had started to fall and dealers were prepared to negotiate. I still own the instrument sixteen years on, and I regard it as a true masterstroke in the history of keyboards. I don’t record much dance music, but if I do, the Prophecy is guaranteed to make its presence felt. I also use it for pretty much all synth lead parts on any type of track, plus of course that electric Rock Bass is never too far from my fingertips. But the greatest benefit to having a Prophecy is that it takes you away from the more complex side of keyboard playing, and allows you to chill out and have some fun. You don’t need to connect it up to masses of studio gear. Just plug it into the stereo, latch the arpeggiator, add some delay, and go. New chord, twiddle knobs, new chord, twiddle knobs… So easy, so therapeutic, and it sounds so incredibly cool.

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