The Korg opsix combines the best bits of FM and subtractive synthesis into one easy-to-use instrument

Hands-on tactility; ease-of-use; warmth, are all terms that you wouldn’t normally expect to associate with an FM synthesizer and yet they’re exactly what the Korg opsix offers… in spades.

Anyone who has attempted to program an FM synth in the past, will have either gotten frustrated or just gave up and walked away. Such was the impenetrable nature of FM synths that most users ended up using the onboard presets without diving any further.

This then gave rise to a whole host of FM-powered synths and keyboards in the ‘80s that were mostly just preset machines which pretty much all sounded the same. It was a good while before different approaches to FM synthesis were attempted.

Much of FM synthesis has relied on a certain understanding of its architecture, which, in a lot of cases, has left users with a machine that has more power under the hood that they’re even aware of.

Korg has taken the humble FM synth back to the drawing board with opsix with one chief aim; to make it easy-to-use. In the process, the Japanese firm has combined the features from subtracted synths that have given the opsix both familiar control and added warmth.

This has been achieved in two main areas of the opsix’s architecture and interface: the operators and processors. The operator mixer is nothing if a revelation for instant control over the carriers and modulators. The intuitive design provides the user with so much surface control that a lot of sound design can be achieved before having to dive further into different menu options.

On the ‘processors’ side of things, the opsix delivers the familiar functionality of subtractive synthesis with multiple filter types including the legendary MS-20 filter, three envelope generators, three LFOs and virtual patching for all your modulation needs.

At the end of the signal chain, as ever, are the effects. With the opsix you get three simultaneous high-definition effects. There are plenty of favourites to choose from, 30 in total, including EQ, chorus, phaser, flanger, delay and reverb effects, with some extras such as a grain-shifter, guitar amp and a master limiter.

All in all, the opsix is a very well-thought-out synth that won’t break the bank, or take much space, but most definitely delivers sonically. For more information, check out the Korg website


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