Korg Radias

Korg Radias Image

The Korg Radias is a Virtual Analog synthesizer that was released by Korg in 2006. It takes advantage of the MMT (Multiple Modeling Technology) that their flagship OASYS synthesizer module employs. The synthesizer itself is similar in design to the MS2000, but offers many more capabilities. It is capable of emulating older digital synthesizers and classic analog synthesizers like the MS-series without any noise or aliasing. The Radias also allows for various external sounds to be fed through its filters and envelopes. It also has the Korg DWGS (Digital Waveform Generator System) that the Korg DW-8000 employs.

The Radias also takes advantage of the KKS (Korg Komponent System) which allows it to be used with the 49-key keyboard or used as a standalone rack module, and the Radias-R unit can be connected to the M3 Music Workstation/Sampler along with its various keyboard models.

Korg Radias Image

The Radias has two oscillators per timbre and a noise generator. Oscillator #1 has nine basic waveforms, with four types of modulation and PCM (64 synth sounds, 128 drum sounds) and Oscillator #2 has four basic waveforms with two types of modulation. The Radias has the ability to stack up to five types of waveforms in Oscillator #1, while using only one voice of polyphony. In Unison mode, you can stack five additional waveforms, while using more polyphony. With this function, you can create some awesome super waveforms-the overall result can contain up to 25 detuned waveforms. The Radias also has two Low-frequency Oscillators (LFO) that add more modulation to the two audio oscillators. These LFO's provide six waveforms and their speeds can be set manually or by tempo.

The Radias itself has four timbres per program. With a timbre, you can assign one drum program, another can have a lead, a bass, and a vocoder as well; all in one program! Each timbre can contain one synthesizer/drum kit, equalizer, and two multi-effects.

The Radias has two filters that can be used side-by-side, individually, or in a series. They offer Low Pass, High Pass, Band Pass, and Combination modes. Each filter offers 24 or 12 dB modes for the low pass filter. The effects on this unit are remarkable as well. The Radias comes loaded with 33 different effects: Delays, Chorus, Flangers, Compressors, talking modulator, and even the good old Polysix Ensemble effect. You can assign one master effect to the program, while each timbre gets its own two effects, creating a whole world of possibilities. The Radias also offers a 16-band vocoder with a nice Formant Motion recording function that allows you to record up to 7.5 seconds of external audio which can then be triggered via the keyboard.

The Radias has a built in arpeggiator as well, providing six different patterns to choose from. Patterns can be up to 32 steps long and the gate/velocity can be set for each step to get that sound you want! It also has two 32-step sequencers (they can be combined for a 64-step on a single timbre). They can easily be assigned to a drum kit, for example, to use the Radias as a programmable drum machine. The step sequencer supports 8-voice polyphony per step.

Korg Radias Image

Overall, this synthesizer is a nice addition to anybody's set-up. It's a good virtual analog that is also quite good for the beginner to learn subtractive synthesis on. Korg also has excellent customer service, and the owner's manual for the Radias is very comprehensive and clearly explains its many functions. The Radias also has a software-based sound editor that is compatible with the newest versions of Windows and OSX. It has been used by Jordan Ruddess and Tangerine Dream.

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127 Visitor comments
August 31, 2012 @ 6:18 pm
Yes Robotunes, it sounds 60% of the time thin and not cool ("not cool" meaning "let me change this lead/bass to that one from Blofeld"). I tried to sell, but no one wants to buy it, so I've been trying to work with the 40%...LOL...The tip is to use the sequencer, the arpeggiator and the modulation sequencer to keep the things moving, and you can add four layers of sounds and effects. You can make a Jarre cover with the Radias if you want to (search Youtube), and it will sound very good. You can buy one of this at Ebay with less than 700 bucks! Depending on the price it can be worthwhile.
August 8, 2012 @ 1:31 am
The Radias is a magnificent piece of gear. Very easy and fun to make sounds, just keep turning knobs until it sounds good. Making a good bass is absolutely possible, but will take practice - detune carefully, use drive, eq and keyboard tracking. Try mixing analog with pcm's, then layer timbres. The vocoder, filter morph and motion record offer several more hours of great experimentation. Don't miss out on this one. I also use a Moog modular and Kronos, and still keep coming back to this for a fresh and different approach to sound design. Its limits inspire, not hinder, creativity.
July 30, 2012 @ 7:26 pm
thin and boring sounds, no matter how much detuning, eq and modulated delay you add. i've been programming analog, fm and additive synths since the '80s, so i know it's not me.

skip this and go for a blofeld with repaired encoders.
June 26, 2012 @ 11:49 pm
OK: 4 timbres (or parts), 2 oscilators, 2 filters and 2 LFOs for each timbre, 3 modulation sequencers for each timbre (12 mod seqs working at the same time), 1 arpeggiator, 2 step sequencers, lots of effects, 2 effects per timbre plus the master effect (9 effects working at the same time), vocoder, a lot of knobs to tweak, and lots of windows in your computer with endless parameters in front of you very well organized to tweak via mouse. The Radias and computer work very nice synchronised.
I can forgive Korg if Radias has a downside.
May 14, 2012 @ 11:51 pm
I might as well be positive. If you hadn't read my last post, this is my only hard synth.

The waveforms, as I had already said, are very clean. No sine aliasing at lower octaves.

The effects are great. Because I obviously don't have anything to input, I can't see how it behaves with external audio, but I have no reason to believe it would be dissatisfactory.

The virtual patches make this machine very flexible, allowing rather complex sounds to be dialed up.

All in all, a very sturdy synth. Perfect for using as a backbone for your studio if you have the time to twiddle the knobs.
VSE Rating


User Rating

Rated 4.21 (585 Votes)

  • Check Price
  • The link above will take you to an eBay search for this synth to see active listings. If you don't find it there, try looking in our forum marketplace or post a wanted classified.
  • Specifications
  • Polyphony - 24 Voice
  • Multitimbral - 4 Parts
  • Oscillators - 2 Oscillators
  • Waveforms - Square, Sine, Triangle, Saw, PCM (Drum and Synths), Formant, Noise, Audio in
  • LFO - 2 LFO's, 6 Virtual Patches, 3 Modulation Sequencers (Waveform, Cross, Unison, VPM)
  • Filter - 2 Filters, -24db/-12db lowpass, high pass, band pass, comb
  • Envelope - 3 Envelope Generators
  • Effects - Delay, Flanger, Vocoder, Talk Modulation, Reverb, Compressor, Phaser
  • Sequencer - 2 32-Step Sequencers (combined for 64)
  • Arpeggiator - Up / Down / Random / Alt1 / Alt2 / Trigger
  • Keyboard - 49 Keys/Velocity Sensitive
  • Memory - 256 Programs, 128 Timbre Templates, 128 Insert Effect templates, 128 Master Effect Templates
  • Control - Midi In/Out/Thru, Keyboard In, USB
  • Date Produced - 2006

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