Tym Mud Fuzz

Here's a Tym fuzz that goes against my usual .... guideline, of a fuzz needing a tone control. 

When I started making fuzzes I really was surprised just how many different fuzz tones there were and how very simple fuzz circuits could be manipulated to give so many options. The more I played with circuits the more I liked the idea of a tone control to move the fuzz from bassy, or muddy, to trebley or sharp. 
I'm a huge fan of the tone control used in the BM circuit. The low pass/high pass filter used in that circuit works really well and it can be manipulated with component values to react differently depending on what you want.

 

After playing around with circuits for a while I came to the conclusion that this circuit worked really well without having to adjust tones too much.
I made a prototype and played around with component values until I had a fuzz I really liked with just one knob.
I don't normally sell prototypes, as I use them to copy, and compare all the "production" ones that follow but I still wanted to play with the circuit a little more and I was feeling particularly upset with the world this day and decided to package it up, with a Tym records 7" and sell it to donate all the money to a refugee centre.

This is a pretty simple little circuit that uses the classic, and very tonally reliable JRC4558 IC as the main drive section. 
Trying to keep it simple to keep a clean and classic tone intact, I started messing around with clipping diodes to find ones I liked with this drive section. I usually use transistors in my fuzzes but I was trying to think outside the box here and the IC gave some really great results.
I settled on asymmetrical germanium clipping as it gave me a slightly warmer, little fizzier fuzz tone than any of the silicon diodes I tried.

 

I sent the idea to Tony who does all my pedal artwork and he was a little stumped at first but liked the idea of one knob to have less impact on his artwork. Then I told him I was going to use one BIG knob. He decided to use the "Mud" part as my Big Muds are kind of the flagship of the whole pedal range.

So, it's simple. It's fuzzy. It's ... simple.

Just plug it in and turn it up, and up, and ... up. The pot is at the end of the circuit and adjusts the amount of volume. The circuit is fairly saturated from the start but about half way through it really starts to pick up in volume and fuzz and get's a little nasty on full. There's unity fuzz from about 4/10 so there's plenty of adjustment on tap, especially for just one knob.

Depending on your amp and guitar this simple little fuzz goes from a thicker fuzzy boost to a full FUZZ with just the twist of that big knob. 
Sharper and slightly thinner with single coils and big fat nasty with high output humbuckers. You can roll off the volume on humbuckers to thin it out or on single coils to clean it up. Depending on the headroom of your amp will depend on just how messy it gets, but, it's a fuzz, so, messy is good.

Dec 09 2015 Written By: Tim Brennan