opsix 37-Key FM Synthesizer (Certified Refurbished)


Sale price$399.99 USD Regular price$599.99 USD
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opsix 37-Key FM Synthesizer features 32 voices of polyphony, 6-Operator FM synthesis, and 5 Operator modes, you can create hundreds of fresh, cutting-edge sounds. Rearrange the building blocks of FM sound, and customize the sound with the front panel controls. Enjoy 30 Effects types and 16 Step sequencer with “logue-style” motion sequencing for maximum expression. Take your music to bold new places with the ease and precision of this versatile synth.


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Get Illuminated with the Operator Mixer

At the heart of every sound is opsix’s Operator Mixer – a simple set of six faders and knobs that invite exploration. Each part lights up red to indicate a sound or blue for a modulator. Changing the position of these controllers opens up new sound-shaping possibilities to breathe fresh life into your musical ideas. This straightforward, hands-on workflow is part of what makes opsix so unique, just like the sounds it offers.

Direct Hands-On Control

Whether you’re tweaking a preset or building a patch from the ground up, the six data entry knobs on the right give you quick access to the parameters you need and seamlessly sync with the large OLED display, giving you a clear, focused direction to your workflow. Coupled with the mixer, it makes creating fresh sounds super easy and, most importantly, fun!

Select from a full range of analog-style filters, from the radical Korg MS-20 low-pass/high-pass filter to the powerful yet smooth Korg PolySix low-pass filter that gives your sound a vintage feel. There are also two- or four-pole low-pass, high-pass, band-pass, and band-reject filters with resonance.

There’s even a built-in spectrum analyzer and oscilloscope that gives you visual feedback via the screen on the music you’re making.

Altered Reality

What started as a legacy synthesis has evolved into something completely different. opsix is FM-based, but the similarities to the classic synthesis end there. The Altered FM architecture delivers sounds across a vast spectrum, far wider than any single synthesis has been able to cover before, thanks to new sound components; new waveforms, filters, shaping, effects, LFOs, envelopes, modulations, and more, all translating to its broad assortment of sounds.

Powerful Effects Processing

opsix provides three blocks of 30 types of high-definition effects that you can use together to enhance your sounds even further. There’s everything from a great mix of usable standard effects like chorus, phaser, delay, and compressor to some world-class shimmering reverbs that will elevate your sound to the next level.

Take true 6-Operator FM to bold new places with 32 notes of polyphony, more FM algorithms and variants to explore, multi-effects, sequencing, and instant, dramatic on-panel sound shaping; its “FM made easy!”

opsix is a digital synth unlike any other, with sounds to match. Instantly explore hundreds of fresh, cutting-edge sounds to inspire your next musical project! Go even further with the power of customization right at your fingertips. Front panel colored controls provide easy access for dramatic shifts in sound characteristics, from icy, sparkling chimes to fuzzy, deep basses. The opsix is an entirely new tool that reveals a world of frequency exploration and a wide range of dynamic possibilities.

  • Opsix makes FM easy by putting Operator editing controls and mixers at your fingertips
  • Altered FM breaks out of the 40 original FM algorithms
  • Lets you redefine the building blocks of FM sound
  • Puts classic FM sounds that you know alongside all-new sounds that bring FM into the modern world
  • True 6-Operator FM with vast expansion (“Altered”)
  • 32 voices of polyphony, up to 8-voice unison
  • Five Operator modes: Carrier/Modulator, Wavefolder, Filter, Filter FM, and Ring Modulator
  • 3 stereo effects processors; 30 Effects types
  • 16 Step sequencer with “logue-style” motion sequencing
  • Virtual patch bay for expressive modulation options
  • 37 Full-size keys