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XILS-lab reincarnates the Polykobol II with new PolyKB III synthesizer

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Out Now

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Laura  Barnes
XILS-lab reincarnates the Polykobol II with new PolyKB III synthesizer

The French software maker is hoping to give virtual and anologue synths a run for their money with its new release.

XILS-lab has lovingly reincarnated the synthesizer that it believes it “should have invented 40 years ago”.

The audio software company’s new PolyKB III is the third software ‘reincarnation’ of the ultra-rare RSF Polykobol II – an analogue programmable polysynth.

XILS-lab claims that the PolyKB III is the most powerful and versatile analogue-modelled polyphonic soft synth available. It faithfully captures the sound and spirit of the ultra-rare RSF Polykobol II, including its most revolutionary feature: aliasing-free, continuously morphing VCOs (Voltage-Controlled Oscillators), which sets it apart from the many ‘run-of-the-mill’ analogue synth recreations already out there.

The oscillators can also be controlled by all modulation sources, so, unlike three-oscillator vintage analogue hardware synths such as the trailblazing Minimoog, for example, endless possibilities abound.

PolyKB III allows adventurous programmers to choose modulation sources, destinations, and amounts from four custom macro modulation matrices.

Each of the four sources can control up to four parameters simultaneously, so 16 additional assignable modulations are available. Amounts can be positive or negative — choose freely between stacks of sources and dozens of destinations, including filter balance for morphing between filters, envelope segments, output levels, and LFO (Low Frequency Oscillator) output levels, etc.

Other specs include the Voice XY pad, a per-voice modulator that affects each note played to sound different from previous and subsequent notes. Space XY, a dynamic stereo modulation pad, allows adventurous PolyKB III programmers to build unique stereo scenes by providing each new note played with a distinct, polyphony-controlled position.

As well as controlling the width of the overall stereo scene, users can control microphone position and direction, and even make the whole stereo scene move courtesy of some suitably chaotic LFO functions.

They can even use the highly-programmable SEQ (sequencer) as a massive modulation-only step sequencer, creating four different sequences of up to 128 steps with each sequencer line controlling up to four different synthesis parameters via User Mod.

Three analogue-modelled envelopes (ADSR1, ADSR2, ADSR3) are ‘hardwired’ to the VCA (Voltage-Controlled Amplifier) and VCF1 and VCF2, but can also be used as modulation sources and destinations, including individual envelope segments, while keyboard tracking is also available for the envelopes.
Effect accesses analogue-modelled vintage Chorus and Phaser effects alongside an analogue-type Delay and dual EQ lending a strong character to PolyKB III’s already unique-sounding sound.

What was it, then, that made the original Polykobol II sound so special, yet still sell so few?

As a 1983-vintage programmable analogue polysynth based on two waveform-morphing, aliasing-free oscillators, and a self-oscillating four-pole low-pass filter, it was superficially similar-looking to Sequential Circuits Incorporated’s innovative Prophet-5 – the world’s first fully-programmable polyphonic synthesizer.

Whereas SCI shipped around 7,500 Prophet-5s during an impressive three-revision, four-year production run, sadly, Serge Fernandez’s RSF SA Synthétiseurs managed a mere 30 Polykobol IIs before running into financial difficulties – hardly surprising given its technical complexity (with 500-plus parts) and attendant (22kg) weightiness with a weighty price tag (equivalent to €6,500 Euro) to match, all of which were hardly in keeping with the-then ‘art nouveau’ digital age of dominating desirable FM (Frequency Modulation) synthesis from Yamaha’s considerably cheaper ‘analogue killer’, the DX7.

What goes around comes around and today XILS-lab’s PolyKB III is all set to give its competitors – virtual and analogue alike – a serious run for their money, without weight issues and at an affordable price for any serious synthesist.

PolyKB III is available now with an introductory promotional price of €119 until January 21st 2017 — rising to €159.00 thereafter.

PolyKB III can be directly downloaded as a multi-format (AAX, AU, RTAS, VST), 32- and 64-bit 16-voice virtual analogue soft synth plug-in for Mac (OS X 10.7 and later) and Windows (XP, 7, 8, 10).

For more information visit


Tags: synthesizer, new gear, XILS-lab, PolyKB III, Polykobol II

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