Low-Pass Filter

LPF filtering Noise, modulated with an LFO (all three are miniMOs)

miniMO's Low-Pass Filter is a voltage-controlled, digital, resonant Low-Pass Filter (LPF).

SOURCE CODE

Download from Github

FEATURES

  • Real time cut-off frequency and resonance control
  • Real time modulation of either frequency or resonance
  • Resonant to the point of self-oscillation: can produce very loud, piercing shrieks 🙂
  • Automatic Battery check

MANUAL

I/O

  • 1&2: Outputs - filtered signal
  • 3: Input for frequency/resonance modulation
  • 4: Input - audio signal

OPERATION

  • Knob: change frequency (default) or resonance
    • miniMO waits until you reach the value it has currently stored
  • Click: toggle between frequency and resonance control
    • The LED blinks once -  frequency control
    • The LED blinks twice - resonance control

BATTERY CHECK

When you switch the module ON,

  • If the LED blinks once, the battery is OK
  • If the LED blinks fast several times, the battery is running low

ACKNOWLEDGMENTS

This filter is based on an algorithm by Rohan Hill, who also kindly helped and gave me feedback throughout its development. Thanks Rohan!