ES2 features two discrete, and different, filters.
Filter 1 can operate as a lowpass, highpass, bandpass, band reject, or peak filter.
Filter 2 is a lowpass filter that offers variable slopes (measured in dB/octave).
Filter button: Turn the entire filter section on or off. Deactivating the filter section makes it easier to hear adjustments to other sound parameters, because the filters always heavily affect the sound. Disabling the filters also reduces processor load.
Filter Configuration button: Switch between a parallel or series filter configuration. See ES2 filter configuration.
Filter Blend slider: Set the balance between Filter 1 and Filter 2. See Crossfade between ES2 filters.
Filter 1 Mode buttons: Switch Filter 1 between lowpass, highpass, bandpass, band reject, or peak filter types. See ES2 Filter 1 modes.
Filter 2 Slope buttons: Switch Filter 2 between different slopes. See ES2 Filter 2 slopes.
Cutoff and Resonance knobs: Rotate to determine the cutoff frequency and resonance behavior of each filter. See Filter cutoff and resonance overview.
Filter Drive knob: Rotate to overdrive the filter, which affects each voice independently. See Overdrive ES2 filters.
Filter FM knob: Set the amount of Filter 2 cutoff frequency modulation with the oscillator 1 frequency. See Modulate ES2 Filter 2 Frequency.