The UPPER FILTER U and LOWER FILTER L section contains five rotary controls and three rocker switches. The FILTER UPPER is a variable resonance Low-Pass filter with either 12dB or 24dB cutoff, whilst the LOWER L is selectable as Parametric Boost or High-Pass. The MASTER rotary pot moves the cutoff frequency for both UPPER and LOWER filters, whilst the LOWER ONLY sets the relative frequency of FILTER L. The Cutoff point coincides if the LOWER ONLY control is set to 8. The UPPER FILTER may be selected as LOW resonance (0.5Q) or VARIABLE, set by the RESONANCE knob. The FILTER LOWER resonance is always set by the RESONANCE control. Both filters may track the keyboard at a rate set by KB AMOUNT, or FILTER L may be set as a static FORMANT filter. In the DYNAMIC setting FILTER L is modulated by the FILTER ENVELOPE as FILTER U. The filters also have an OVERDRIVE setting for extra fuzz!