wmd-synchrodyne

WMD Synchrodyne

VCO + PLL frequency multiplier + switched-capacitor filter sound source

14 HP Eurorack module

The WMD Synchrodyne is a multi-part experimental voice that chains a sawtooth-core VCO into a Phase Locked Loop (PLL) frequency multiplier/divider, which in turn clocks a switched-capacitor multimode filter (SCF). The VCO's pulse output drives the PLL; the PLL multiplies/divides that frequency to clock the filter so the VCO simultaneously acts as audio source and filter-tracking control. Track Speed, Damping and Influence shape how aggressively the PLL locks, giving it slew, self-FM and over-tracking behaviors. A front-end VCA + four-stage wavefolder feed the filter, and single-stage wavefolders sit on the -12 dB and -24 dB taps for added grit. Designed to be pushed into instability and self-oscillation.

Features

  • Sawtooth-core TempCo VCO with range ~0.02 Hz to over 400 kHz
  • Calibrated 1V/oct input and rising-edge hard-sync input
  • Linear (AC/DC) and exponential (DC) FM with bipolar attenuators
  • Phase Locked Loop frequency multiplier/divider
  • Selectable multiply (x2-x1024) and divide (div 2-9) ratios via rotary switches
  • Variable Track Speed and Damping for PLL slew, self-FM and over-tracking
  • Influence CV input to perturb and animate the PLL lock
  • Phase Delta output reveals PLL lock state with self-PWM
  • Switched-capacitor multimode filter (LP/BP/HP) with 50:1 / 100:1 ratio
  • Simultaneous 2 Pole (-12 dB/oct) and 4 Pole (-24 dB/oct) outputs, 180 degrees out of phase
  • Stable self-oscillation, most prominent on the 4 Pole output
  • Voltage control of filter resonance via attenuated CV input

Controls & Jacks (33)

  • Multiply
  • Multiply Fine
  • Divide
  • PLL Out
  • Phase Delta Out
  • Influence In
  • Influence
  • Track Speed
  • Damping
  • CLK In
  • Filter Mode
  • Filter Ratio
  • Fold
  • Filter In
  • Resonance
  • VCA
  • Resonance CV
  • VCA CV
  • Resonance CV In
  • Coarse
  • Fine
  • Exp FM
  • Lin FM
  • Sync
  • 1V/Oct
  • Exp FM In
  • Lin FM In
  • 2 Pole Out
  • 2 Pole WaveFold Out
  • 4 Pole Out
  • 4 Pole WaveFold Out
  • Saw Out
  • Pulse Out

How-To Guides

  • Self-Oscillating Filter Drone
  • Pitch-Tracked Filter Voice
  • Over-Tracking Chaos
  • Wavefolded Distortion
  • External Clock as Filter Source

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

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