Input

Allows you to control the input gain of the EQ to prevent the possibility of clipping.

Phase Invert

Allows you to invert the phase (polarity) of the input signal in order to change frequency response between "multi-miked" sources (a common technique for "miking" a guitar amplifier), or to correct for miswired microphone cables.

Type

Allows you to select an EQ type (High-Pass, Low-Shelf, Peak, High-Shelf or Low-Pass).

Gain

Allows you to control the amount that the selected frequencies are cut or boosted (for Peak, High-Shelf, and Low-Shelf only).

Freq

Allows you to designate the center of the frequency region to be cut or boosted.

Q

(Peak only) Allows you to set the bandwidth of the Peak filter. Higher values represent narrower bandwidths. Lower values represent wider bandwidths.

Bypass

Bypasses the EQ. The 4-Band EQ II has individual Bypass buttons for each band (black buttons with EQ curve icons).

High-Pass

Attenuates all frequencies below the selected cutoff frequency setting at a rate of 12ádB per octave while allowing all others above the frequency to pass through. For this reason, no gain control is available for this filter. High-pass filters can be useful for removing low-frequency rumble or for thinning out the lower end of a sound for special effects, such as a "telephone simulation" effect.

Low-Shelf

Produces a lift or a cut below the specified frequency.

Peak

Boosts or cuts only those frequencies around the selected center frequency. The Q button sets the bandwidth of the Peak filter, which determines the width of the filter's overall slope — from a broad "bell" shape to a narrow notch. Broad curves tend to be most useful for musical applications. Narrow curves are useful for special-purpose processing such as hum removal. Higher values represent narrower bandwidths. Lower values represent wider bandwidths.

High-Shelf

Produces a lift or a cut at the specified frequency and above it.

Low-Pass

Attenuates all frequencies above the selected cutoff frequency setting at a rate of 12ádB per octave while allowing all others below the frequency to pass through. For this reason, no gain control is available for this filter.