The Electro-Harmonix Metal Muff with Top Boost features 3 powerful EQ bands that are ideal for sculpting mids and a total of 6 controls for shaping sound precisely your way. Top Boost adds serious bite with its own control knob and footswitch button. High input impedance buffered bypass Output volume and master drive controls 3-Band EQ: bass, mid and treble Foot switchable Top Boost with separate control knob Knob controls include Distortion, Bass, Midrange, Treble, Top Boost and Output volume. The unique Top Boost knob allows you to dial in frequencies that center between 3.5 kHz & 4.3 kHz Buffered Bypass