Darkglass MTB7K Microtubes B7K ULTRA Bass Overdrive Pedal w/ 2 Patch Cables Controls: Master, Blend, Level, Drive, Bass (+-12dB @ 100Hz), Lo Mids (+-12dB switchable 250Hz, 500Hz and 1kHz), Hi Mids (+-12dB switchable 750Hz, 1.5KHz and 3kHz), Treble (+-12dB @ 5kHz) 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. Grunt Switch: Sets the amount of low frequency content to saturate by selecting between three different bass boost levels before the clipping stage. Direct Output: A balanced version of the " output, useful for running into PAs or studio mixing consoles.