Included in: VultCompacts

Vorg is a low/high pass filter based on a modernized Operational Transconductance Amplifier version of the MS-20 filter. Vorg is the first module that I developed with the idea of making it feel exactly as a real eurorack module. This considers the spacing between the knobs and sizes. Vorg is also part of Freak. Using it with Freak allows modulating the Resonance and Drive controls.


  • Cutoff: Defines the frequency at which the filters starts attenuating frequencies.
  • CV1 & CV2: these pairs of input jack and attenuation knob are the modulation sources for the Cutoff control. Notice that the knobs are attenuators not attenuverters.
  • Resonance: the resonance boost the frequencies near the cutoff frequency. Increase this knob and you will hear the personality of the filter. After some point the filter will start self-oscillating and can be used as a sound generator.
  • Drive: controls the amount of signal that enters to the filter. Increasing the drive will cause the filter to saturate which adds interesting harmonics to the sound.
  • Mode: pressing the button switches between low pass and high pass filter mode. The current mode is shown by the LED lights in the panel.
  • In: input to the filter.
  • Out: output of the filter.

Patching Tips

The filter section in the real MS-20 consists of two filters: one HP and one LP. You can easily recreate this behavior with Vorg by creating two instances and experimenting different ways of connecting them.


Making of Vorg

These are the slides I prepared for a presentation where I talk about the process of modeling Vorg.

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