The Ugly Face has an interesting set of options. The Threshold knob has to be the most interesting though least useful. Last year I thought I’d add a tone control in it’s place. I wanted to build an Ugly Face and keep it in 1590B sized box. This format makes it hard to fit more than 4 Knobs. I decided to drop the Threshold and replace it with a Big Muff style tone control.
This was a pretty easy project, I already had a PCB and all of the parts on hand. The PCB I had did not have any space for the tone control. The Big Muff tone control requires, besides the pot, fours parts, two resistors and two capacitors. I remembered seeing an article on the Big Muff tone control over at Beavis Audio research where they mentioned soldering all of the parts on to the pot. I thought about this but decided against it. I have been using and planned to use these 12MM pots. Which seemed too small. Plus the box was going to be a little crowded and didn’t want to risk the parts shorting against something.
[picture of 12mm pot]
I decided to mount the tone control on a tiny piece of perfboard.Using small multilayer ceramic caps would make the whole thing fit easily.
[image of perf layout.]
Last was to run the output of the Ugly Face into the tone control before going to the volume.
[Picture the interior of the box]
I decided to do this box in a plush purple fur.