The G4EQA is a 1/3 octave equalizer covering the full audio frequency spectrum. Twenty-eight individual sliders—ranging from 30 Hz to 16000 Hz—give you the choice to boost or cut specific frequencies + 12 decibels. Use the G4EQA to minimize or eliminate microphone feedback, or create a natural sounding environment. Low and high frequency filter switches provide cut off for the extreme ends of the usable frequency range. With over a half-century of experience in the industry, Grommes~Precision backs the G4EQA with its unbeatable expertise and Precision Assurance Pledge: a 5 year warranty and a 30 day money back guarantee.