Korg Opsix FM Synthesizer

True six-operator FM synthesis, and more

The opsix is a new digital synthesizer that features our newly designed six-operator sound generator. Although the instrument has a six-operator FM sound structure like classic FM synthesizers, the opsix doesn't just reproduce their sounds—it totally reimagines them! With a diversity of waveforms, operator modes that go beyond the realm of FM, and a filter that brings together a fusion of subtractive synthesis, opsix makes tames complexities of FM so that you can focus on exploring sounds instead of programming them. Simply put, opsix offers the editing simplicity of analog synths to control the power of arguably the deepest type of digital synthesis.

FM exploration, easier than ever

Musicians today use hardware-based digital synthesizers to achieve a level of operability that just cannot be found with software-based instruments. The six sets of knobs and sliders on the opsix panel, as well as the operator mixer, are symbolic of this fact. Korg’s volca FM was the first FM reimagination that helped to bring the most dynamic parameters of FM to the surface, and we expand upon that with opsix’s workflow.

The knobs and sliders with two-colored LEDs on the opsix let you quickly and clearly see the relationships between operators, whose roles change with each algorithm. This lets you make direct changes to the pitch and volume for carriers, and to the brightness of the sound or the strength of the harmonics for the modulators. These controls give you sonic control over the unpredictability of FM just by subtracting and adding sounds as if you were using a mixer or drawbars!

Full editing with the DATA ENTRY knobs

To add to the six operator mixers, the opsix features several knobs on the right side of the panel. Use the six DATA ENTRY knobs for full editing without minimizing or summarizing any information. Taking a look at these controls, you might think back to the days when traditional FM synths were more difficult to operate. Back then, you had to move through massive numbers of pages, and couldn’t figure out where you were in the overall scheme of things. Rest easy—with the opsix, we’ve taken away these worries. You can now edit without getting lost, thanks to the combination of six graphical parameters on the large OLED display at the center, and the rotary encoders.

The HOME/ALGO page is the starting page for everything on the opsix, and features major parameters including algorithms, EGs, and effects. Use this page with the operator mixer to get started with everything you need to do.

Wide range of modulation

The synthesis offered by the opsix is made even more powerful with the processors that come at the end of the signal chain. The MOD section works separate from the operators, with three EGs and three LFOs; and 12 virtual patches make a wide variety of routing possible. Use these features for a huge range of modulation to create swelling or add rapid motion to your sounds.

Powerful Filters

In contrast to FM, the FILTER section follows your creation of sounds by offering analog synthesizer-like subtractive synthesis. Select from a full range of filters you want to use, from the radical MS-20 low-pass/high-pass filter, to the powerful yet soft Polysix low-pass filter that gives your sound a “vintage” feel; as well as two- or four-pole low-pass, high-pass, band-pass and band reject filters with resonance.

A treasure-trove of effects

The high-definition effects you’ll find on the opsix can be used right away in recording. The instrument offers three series (which can be used simultaneously) of 30 different effects; from including standard effects like a compressor, EQ, chorus, flanger, phaser and stereo delay, to distinctive effects like rotary speakers, grain shifters and more... as well as shimmering reverb effects that add a new dimensions to already awesome sounds.

Spectrum analyzer and oscilloscope

The analyzer built into the opsix is a must-have feature for visualizing FM synthesis. It shows output levels for each frequency band, so that you can see the distribution and changes to the harmonics at a glance that are caused by modulation. The opsix also features a built-in oscilloscope that lets you check the output waveforms. The colorful changes to the sound and visual feedback are sure to draw you into a deep “synthesizer vortex”!

Powerful 16-step polyphonic sequencer

The 16 buttons on the bottom right-hand part of the panel glow green with the colors that evoke FM synths, while providing you with a multipurpose 16-step sequencer. With this onboard polyphonic note sequencer, you can record up to six notes per step, and edit the velocity, gate time and playback timing for each note. This lets you create long phrases or make subtle shifts in timing to emulate strums or drum rolls, something that’s not possible on a typical 16-step sequencer. Also, the motion sequencer of the opsix lets you record changes of up to six parameters, creating smooth motion changes in sound within a phrase, or building rhythms that change dramatically with each step.

While the opsix has an easy-to-use 37-note keyboard, it also features a sequencer that rivals that of grooveboxes. Just press the PLAY button—you’ll be floored by the power that this sequencer lets you unleash.

Adding unpredictability to sounds with the Randomize feature

Use the Randomize feature as found on the wavestate if you’re in the mood for unexpected sonic discoveries. Press the button marked with the die icon to generate a newly randomized sound. You can use the Randomize feature for the entire sound, or just for the operators, the algorithm or the sequences. Use the randomized sounds as-is or edit them as you like—the sky’s the limit.