Auburn Sounds

Pitched percussive synth


GFM Koch is a physical synthesizer able to generate the punchiest percussive notes, by construction. Listen to audio examples...

Thanks to the purity of its integration, its sound is especially crystalline from the lowest to the highest frequencies. Thus it is suitable for sub-bass stabs, percussive basses, emulating electric pianos and tonal percussions.

To compliment this raw sound, a sub-oscillator and voice-wise distortion is provided. This distortion is devoid of aliasing, again by construction.


  Sound samples

Tommy garcia— 7.25.13 Lullaby
A track with 4 Koch instances.
Koch demo track
Various sounds made with Koch, plus a hi-hat.

How to use it?


Koch usually generates a lot of low frequency energy. Better use your preferred high-pass filter behind.

Not too fond of Koch note envelope? Use a compressor behind Koch to tame the dynamics.

  Customers quotes

“ I recently stumbled upon your free Koch VST (as well as the other two) and I'm having a blast with them! ”


Get it now!

platforms supported
Koch is available as a free VST 2.4 and Audio Unit plug-in for Mac and PC (32-bit & 64-bit).
  Download Full Version


This plugin is free but unsupported. It won't receive neither support nor updates.