Crazy Tube Circuits Motherload

The Crazy Tube Circuits Motherload is an intriguing take on the hybrid distortion/fuzz pedal that borrows from two iconic circuits (the Muff and the Rat) to offer at once some old and new sonic flavors.

This is not a dual-channel pedal, but rather a one-channel dirtbox with a range of voices.

The toggle switch on the top center of the pedal allows the player to choose the pedal’s dirt flavor, R is for Rat-style, while M is for Muff-style, a distortion and a fuzz circuit that complement each other well but are rarely used together.

Each mode features the EQ control found in the original that’s only active when the respective mode is selected: a Tone knob for the Muff and a Filter knob for the Rat, working anti-clockwise like in the original. There’s also a Muff-only Voice knob that cycles through various versions of the classic Electro-Harmonix fuzz.

To make things a little more interesting and complex, the builder added a white push button called EQ Link, located at the bottom of the EQ controls, which allows to blend the two circuits’ EQ sections, opening up some new sonic possibilities.

With this function activated, it’s possible to use both EQ controls (Tone and Filter) in either mode, and the Voice control also in Rat mode, for some unique sculpting.

For the true geeks, Christos from CTC has created a page in which he explains the thinking behind the Link EQ feature, here with schematics and a more in-depth explanation of the functions.

You can hear the tones created by this interaction in the videos below.

Crazy Tube Circuits Motherload, Builder’s Notes

Motherload pays homage to the classic fuzz / distortion pedals that set the benchmark of saturated guitar sound. At the heart of this pedal, you will find two distinct all analog circuits inspired by the Holy Grail of Big Muff® and RAT® designs.

R circuit goes from a touch of overdrive all the way up to roaring distortion. The filter knob is there to ensure that you will smooth out high frequencies or cut through the mix when needed.

M side is the classic fuzz distortion beast you would expect but with great string separation and rich in harmonics for almost infinite sustain. The tone knob is the classic muff style knob while the voice knob helps you cycle through the wide spectrum of muff design variations.

Each circuit is independent from the other with its own EQ control(s) until…you hit the LINK EQ button. This is where all the magic happens! Now all the EQ controls are active in both circuits and a whole new sonic palette is revealed.