Lovepedal bumph.
This handmade guitar pedal features a three way toggle switch that allows you to change tones from 5E3 Woody (Tweed Fender Deluxe), High Power Twin (50's Fender Twin) and Master Volume Tchule (combination of both the 5E3 Woody and the High Power Twin). The amount of gain is controlled by the first knob. The second knob is a second gain stage which emulates what happens when you crank one of these vintage low wattage amplifiers.
Purple = Purple plexi?