The Hot-Rod Plexi distortion pedal is inspired by vintage amps of the same nickname that transforms any amp into a modded-out, roaring Plexi head. Plexi's are known for tight responsiveness and the classic roar and volume that brings the toughest guitarist to their knees. Tone seekers used to take the legendary Plexi heads (tremolo version) and replace the tremolo circuit with an extra 12AX7 preamp tube to "hot rod" the gain stage. While those hulking stacks are known to sound best cranked up to ear-bleeding levels, this pedal can painlessly transform your existing amp without lifting a finger. With the Hot-Rod Plexi, you can completely change the personality of a clean amp or use it as an instant mod to a dirty amp.
In Stock mode, it's as if you have the signal path from the input jack to the speaker jack (without the speaker emulation) of a stock ‘68 Plexi. Hot engages an extra "12AX7" pre-amp gain stage. With its own level control, Hot can kick in up to 28dB of pre-amp boost -- a pretty insane amount of gain. The Thump control adds the low end found in a sealed 4x12" cabinet so that even an open back combo amp can sound like a half stack.
Portions of Tech 21's SansAmp technology have been incorporated into the Hot-Rod Plexi to generate organic tube amp distortion characteristics
Tone is a very musical, specialized low pass filter that cuts the high end without losing mids or getting muddy
Drive adjusts the overall amount of gain and overdrive, similar to when the output section of a tube amp is being pushed
Thump takes care of the low end for the resonant frequency of a 4x12 cabinet