Based on the 1969 Pre Big Muff circuit with an added midrange knob. Basically a refined big muff sound with a more defined bottom end and a distortion like growl. A faster attack and the ability to cut through a mix due to the variable mid knob. Scooped mid sounds are on tap as well. Tone and mid knobs give a lot of tonal variation. Lower gain settings are possible with the same presence as high gain settings!