This UGen contains virtual analog low pass, band pass and high pass filters based on the ground breaking work of Vadim Zavalishin (https://www.native-instruments.com/fileadmin/ni_media/downloads/pdf/VAFilterDesign_1.1.1.pdf). The filters here are fairly cheap in CPU usage and behaves well throughout the frequency spectrum and under modulation.
Ported from https://codeberg.org/nonmateria/folderkit.
Cutoff / center frequency (depending on type) in herz. May be modulated at control rate.
Resonance. Range: 0.0 to 4.0.
An integer that sets the filter up as one of the following types: 0 = LPF2 1 = LPF4 2 = BPF2 3 = BPF4 4 = HPF2 5 = HPF4