Level Sets the volume of the overdriven signal. Drive Sets the amount of saturation in the overdriven signal. Blend Mixes the clean input signal with the overdriven signal. The clean signal remains at unity gain while the volume of the overdriven signal is set by the Level knob, allowing for fine control of the blend ratio. Grunt Switch Sets the amount of low frequency content to saturate by selecting between three different bass boost levels before the clipping stage. Attack Switch Sets the amount of treble content to saturate: The "Boost" setting emphasizes the treble content extra clarity and presence. The "Flat" position leaves this register untouched while the "Cut" position will reduce the amount of high frequencies being saturated.This new addition helps to keep the treble portion of the signal under control, specially useful when playing with new strings and/or cabinets with tweeters! Low +-12dB @ 100Hz Low Mids +-12dB @ 500Hz Hi Mids +-12dB @ 1.5kHz Treble +-12dB @ 5kHz Parallel Output A passthrough for your input signal, useful for parallel processing. Direct Output A balanced version of the ¼” output, useful for running into PA’s or studio mixing consoles. Dimensions 12×10.7 cm (4.72×4.21 in)