make-noise-moddemix

Make Noise ModDemix

Dual Thru-Zero VCA, ring mod, and VC mixer

6 HP Eurorack module

The modDemix is a dual direct-coupled amplitude modulator and voltage-controlled mixer for Eurorack synthesizers. Each channel functions as a Thru-Zero VCA capable of ring modulation, balanced modulation, CV multiplication, and voltage-controlled polarization. Its musical character ranges from clean VCA duties and smooth crossfading to clangorous, inharmonic ring modulation timbres and demodulation distortion.

Features

  • Two identical direct-coupled amplitude modulation circuits usable independently or together
  • Thru-Zero VCA behavior: output phase inverts when Carrier/CV crosses zero volts
  • Works at both audio rate (ring modulation) and control rate (CV multiplication)
  • Carrier/CV Strength attenuator normalized to +5V for unipolar manual control when no CV is patched
  • Signal 2 IN normalled to Signal 1 OUT for series (modDemod) operation
  • SUM OUT mixes Signal 1 OUT, Signal 2 OUT, and AUX IN
  • AUX IN allows chaining multiple modDemix or Optomix units for larger mixes
  • Four-quadrant LED indicators per channel showing amplitude and phase of both signal and carrier
  • Capable of standard AM, balanced modulation, single-sideband, double-sideband, ring modulation, VCA, voltage-controlled mixing, crossfading, panning, and CV multiplication

Controls & Jacks (18)

  • Carrier/CV 1 Strength— Attenuator for Carrier/CV input to Channel 1. Normalized to +5V; acts as unipolar manual control when nothing is patched. Range 0V-5V.
  • Carrier/CV 2 Strength— Attenuator for Carrier/CV input to Channel 2. Normalized to +5V; acts as unipolar manual control when nothing is patched. Range 0V-5V.
  • Signal 2 OUT— Modulated output from Channel 2.
  • SUM OUT— Mix of Signal 1 OUT, Signal 2 OUT, and AUX IN.
  • AUX IN— Auxiliary input to summing stage. Allows for chaining of multiple modDemix or Optomix units to create larger mixes.
  • Carrier/CV 2 IN— Determines amplitude and phase of Signal 2 IN.
  • Carrier/CV 1 IN— Determines amplitude and phase of Signal 1 IN.
  • Signal 2 IN— Signal to be processed on Channel 2. Normalled to Signal 1 OUT.
  • Signal 1 IN— Signal to be processed on Channel 1.
  • Signal 1 OUT— Modulated output from Channel 1.
  • Channel 1 LED Lower Right— Lower-right indicator in Channel 1's four-LED signal display.
  • Channel 1 LED Upper Left— Upper-left indicator in Channel 1's four-LED signal display.
  • Channel 2 LED Lower Right— Lower-right indicator in Channel 2's four-LED signal display.
  • Channel 2 LED Upper Left— Upper-left indicator in Channel 2's four-LED signal display.
  • Channel 1 LED Upper Right— Upper-right indicator in Channel 1's four-LED signal display.
  • Channel 2 LED Upper Right— Upper-right indicator in Channel 2's four-LED signal display.
  • Channel 1 LED Lower Left— Lower-left indicator in Channel 1's four-LED signal display.
  • Channel 2 LED Lower Left— Lower-left indicator in Channel 2's four-LED signal display.

How-To Guides

  • Classic VCA with Envelope
  • Classic Ring Modulation
  • Ring Modulation with Root Tone
  • Tremolo to Amplitude Modulation Spectrum
  • modDemod Demodulation Distortion
  • Voltage Controlled Crossfader
  • Voltage Controlled Panning
  • DPO Supersaw via Voltage Controlled Inversion
  • 4-Channel Voltage Controlled Mixer via Chaining
  • CV Multiplication for Pitch Transposition
  • Octave Up Doubling

Explore the interactive ModDemix panel on BleepDex — tap any control to learn what it does.

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