Making Sound Machines Farb Highpass
Analog Transistor Ladder Highpass Filter with Tilt and Resonance CV
4 HP Eurorack module
Analog transistor-ladder highpass filter for Eurorack, with Tilt EQ frequency bias and voltage control of cutoff and resonance.
Features
- Tilt EQ frequency-bias stage with CV-controlled cutoff and resonance.
- Resonance can drive the filter into self-oscillation.
Controls & Jacks (7)
- Resonance— Sets resonance emphasis at the cutoff frequency; higher settings cause self-resonance.
- Audio Out— Provides the processed highpass-filtered audio signal.
- Resonance CV— Receives 0–10 V control voltage for resonance; the Resonance control scales the incoming CV when patched.
- Cutoff— Sets the highpass cutoff frequency, sweeping from a neutral timbre toward a bright sound with only high overtones at maximum.
- Audio In— Receives the audio signal to be processed; expects a -5 V to +5 V signal range.
- Cutoff CV— Receives 0–10 V control voltage for cutoff; the Cutoff control becomes a CV offset when patched.
- Tilt EQ— Sets the tilt-EQ frequency bias: counterclockwise emphasizes bass warmth, clockwise boosts treble brightness, and 12 o’clock is neutral.
How-To Guides
- Basic highpass sweep
- Play self-resonance
- Sample-and-hold dual modulation
Explore the interactive Farb Highpass panel on BleepDex — tap any control to learn what it does.