Filter
Low-pass filter variant used for additional filter states/instances. It is useful when several filters must run independently in the same formula.
Cutoff is normalized; start around 0.02 to 0.35 for musical results. Resonance/Q is typically 0.0 to 0.9. Keep extreme feedback/resonance values under control.
fs(saw(X), 0.05+0.25*param(2), 0.25)
For pitched oscillator functions, X already contains the current MIDI note pitch and transpose information. Prefer saw(X), sin(X), or pwm(X, 0.4) unless you intentionally want an octave or ratio shift such as 0.5*X or 2*X.