Flow 3

Flow 3

AUTO-DYNAMIC FILTER

6 HP | +12: 45 mA, −12: 45 mA | JORF3
User Manual (PDF) | ModularGrid


Available exclusively through our authorised dealer network.


Flow 3 is a filter that sounds bigger than it looks. Behind the compact 6 HP front panel lies a novel variation on the classic state variable filter topology, offering simultaneous lowpass, bandpass and highpass outputs. Core integrator saturation provides for a sound that’s clean, yet distinctive.

The resonance response is exceptionally smooth—and it can easily reach self-oscillation. In this mode, temperature-compensation and exact calibration make Flow 3 a reliable quadrature sine/cosine oscillator with tight pitch tracking.

But the ace up Flow 3’s sleeve is its auto-dynamic nature: it is a filter that can modulate itself. This is achieved by a combined decay generator/envelope follower circuit which controls the filter frequency over an adjustable range. Either fire decay envelopes from external triggers, or flip it to auto mode to follow along with the incoming signal’s amplitude envelope (or both, simultaneously).

Creating heavy-hitting analogue kick drum sounds becomes a breeze. And with a bit of patching, Flow 3 can even be used as a spectrum splitter (or ‘crossover’), cleanly separating the full audio range into low and high portions, for dual-band signal processing. This is possible thanks to the Linkwitz-Riley filter response at minimum resonance.

Let yourself get carried away as Flow 3 takes the old auto-filter concept to new voltage-controlled heights.


  • Analogue state-variable VCF with self-oscillation capability.
  • Core integrator saturation adds distinctive character.
  • Extra-smooth resonance with voltage control input.
  • Filter outputs: 2-pole lowpass, 2-pole bandpass and 2-pole highpass.
  • Self-oscillation: quadrature sine/cosine waves, separated by 90°, with temperature-compensated 1 volt per octave tracking.
  • Integrated voltage-controlled decay generator/envelope follower for self-modulation.
  • Decay circuit driven by external triggers and/or incoming signal amplitude.
  • Envelope output can modulate other modules in tandem.
  • Linkwitz-Riley crossover response unlocks dual-band processing possibilities.
  • Impedance-compensated outputs with dual-colour vari-wave LED.
  • Trim potentiometers accessible from the front panel.
  • Precision-milled 2 mm anodised aluminium front panel with high-resolution, non-erasable graphics.
  • Bullet-proof design: polarised power header and MOSFET protection circuit.
  • Includes 16-to-10-pin Eurorack power ribbon cable.
  • Premium mounting hardware: black screws, black nylon washers and matching hex key.
  • High-quality components and assembly; designed and made in Belgium.


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