Korg opsix: Exclusive Synth and Software Review

Mark Jenkins checks out whether this intriguing new FM synth is a blast from the ’80s, or much more.

The Korg opsix FM synth is one of a pair of new compact, lightweight 3-octave synths from Korg that hark back to the ’80s. (The other is the Wavestate, Synth and Software review to follow shortly.)

The opsix stems from Dr. John Chowning’s techniques of FM synthesis. Initially found on Yamaha’s world-beating DX7, FM launched a generation of precise, metallic sounds quite some distance from the analog textures of the time.

FM synthesis has been quiet recently, though, in the wake of a revival in analog sounds, and has been mostly heard only in the form of software. But now Yamaha has a compact FM synth, the Reface DX, and on the opsix Korg claims to offer “altered FM.”

What’s so altered about it? Well, the basic FM sounds are there – in fact the opsix has some compatibility with original DX7 presets – but they’re much more accessible, with six rotary controls governing the pitches of the xis oscillators per voice (whether they’re set as audio oscillators or modulation oscillators), six sliders governing their level, and 6 data controllers which (in various modes) edit sounds, edit effects, and even edit filters (more on that below).

Choose from the 40 available algorithms that determine how the oscillators are used for audio or modulation, or set up a User one of your own, then twirl the controllers to get endless variations on metallic, swooping and twirling textures, helped by on-board effects that include delay, reverb, distortion, phaser, and more. Or try completely initializing the setup, which gives random sounds you can work with as the basis for your own sound creation.

The opsix Sequencer offers 16 polyphonic steps, and its illuminated buttons double as selectors for four banks of 16 favorite sounds – very useful on stage. And if you find the FM textures a little too sharp or metallic, you can now apply analog-style filtering of various types (highpass, lowpass, Korg MS20 style and so on) and even tweak resonance, just like on an analog synth. A facility called “Analyzer” turns the LCD display into a spectrum analyzer, giving some idea of what’s going on within each sound.

FM synthesis has always been considered very strong at bass sounds, and combined with these analog-style filtering capabilities there’s huge potential for techno and IDM textures. That’s before you even start up the arpeggiator, which can be latched so it plays when you’re hands-free.

The opsix switches up and down in octave to make up for the short keyboard, and the rear panel offers MIDI In and Out, USB, stereo audio, and headphone outputs, as well as a socket for a small external power supply. It’s a shame it doesn’t have an option for battery power.

Dive deep into the menus and you’ll find options for external synchronisation of the sequencer and arpeggiator, as well as displays to help build up new sequence and arpeggio patterns.

Those who didn’t experience the arrival of FM synthesis first-hand will find great novelty in the OP6 sounds, and others will welcome the addition of analog-like textures. Compact and lightweight, the OP6 is a flexible and maybe sometimes surprising option both for stage and studio use.

For more information on the Opsix

Video review by Mark Jenkins – www.markjenkinsmusic.com

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