Graphic EQ

Useful for simple frequency sculpting, a good Graphic EQ can find a place in almost any pedalboard. Graphic EQ can wring a variety of tones out of other pedals (such as when placed before Distortion effects). The EQ can also be used as a signal booster when positioned in front of amps. 

Shelf - Boost or cut of all frequencies below (in the Low band) or above (in the High band) the chosen frequency. 

Peak - Boost or cut of a band of frequencies centered on the chosen band frequency, the width of which is controlled by the Q control. 

Low-Pass (High band) or High-Pass (Low band) - Cuts frequencies above (Low-Pass) or below (High-Pass) the selected frequency, with a choice between 6 dB, 12 dB, or 24 dB- per-octave curves. 

Notch - Rejects frequencies around the chosen EQ frequency, with bandwidth control via the Q control. 

Based on the Graphic EQ—Avid custom filter

The Eleven Rack Graphic EQ gives you full control over five bands of EQ—100 Hz, 370 Hz, 800 Hz, 2 kHz, and 3.25 kHz. It's ideal for cutting out troublesome frequencies or dialing in just the right tone.