- Sensitivity: Determines when the effect will trigger
- Peak: Boosts the center frequency for a more dramatic filtering (like a Resonance control on a synthesizer)
- Filter (LP/BP/HP): Selects the type of filter — Lowpass, Bandpass or Highpass
- Drive (Up/Down): Selects the direction of the filter sweep — upwards or downwards
- Range (High/Low): Selects the frequency range of the filter
A review of this effect as well as later models can be found here.