This is my entry in the End of Days Fuzz Challenge 2022. Based on the Fuzz Face with an added two band tone control similar to the tone controls on Orange and Ampeg amplifiers.
I wrote about this circuit in this post: The Sultan. I was pretty happy with the sounds on the breadboard so I decided to create a prototype PCB. I used PCBWay.com. Their prototyping service is $5 for 5 or 10 boards (always order 10!)
Changes
I got some great advice over at DIYStompboxes.com forum and made a few improvements. Here’s a link to a thread on this topic.
Here is the current schematic. It’s a silicon fuzz face with a James tone control and an extra transistor to make for the volume loss of the tone stack, and bring down the output impedance. I borrowed the “pinch” control from the Zvex Wooly Mammoth, I called this “width”.
The Build
The build went together well. I like designing boards with pots and LED mounted to the board. Placing the offboard wiring along the bottom edge makes for easy wiring!
I always include pads for IN, OUT, LED, and GROUND, along with a pad for the input jack ground and output jack ground. On this board I made a mistake and connected these two pads to one another and NOT to ground, oops.
Looking the Schematic in Eagle it looked like the pads were connected correctly. But after moving the two pads I saw that they were connected to each other and not to anything else.
Assembling thew board
I populated the PCB. The layout worked well with all parts fitting comfortably.
Getting three 16mm pots in a row to fit a 1590B enclosure works but, you must take the plastic dust covers off!
Making the enclosure
I milled a black powder-coated a 1590B enclosure. This design is going in a good direction but needs another revision.
Wiring the box
Next I put everything in the box and wired it up.
I gave it a test and it wasn’t working. 😕
After a few minutes of troubleshooting I realized the mistake with the input and output jack ground pads.
There is another ground connection for the LED switch. I ran a wire from this through the ground connection on the jacks to the switch, and everything was sounding fuzzy! 🤘
The last step was to put some knobs on and close up the box. I’m running low on knobs! I couldn’t find 5 matching so I went with 5 different colors!
Conclusion
This sounds pretty good. The tone control pushes past the standard fuzz face sounds. The “width” control adds some zippery and splatty fuzz tones.
The tone control provides access to some sub-bass sounds and thinner sharper tones. You can also dial in a mid scoop or mid hump if you like. It’s very versatile.
If you like the Fuzz Face sound you might like this with the added tone versatility.
| Part | Value |
| BASS | A1M |
| VOLUME | A100k |
| SQUINCH | B500k |
| TREB | A470k |
| C1 | 220n |
| C3 | 100µ |
| C4 | 100µ |
| C5 | 100n |
| C6 | 220n |
| C7 | 1n |
| C8 | 1n |
| C9 | 500p |
| C10 | 5n |
| C11 | 220n |
| C12 | 220n |
| C13 | 470p |
| C14 | 50p |
| D1 | 1N5817 |
| D2 | LED |
| GAIN | B2k |
| Q1 | 2N3904 |
| Q2 | 2N3904 |
| Q3 | 2N3904 |
| R1 | 1M |
| R2 | 47k |
| R3 | 100k |
| R4 | 2k2 |
| R5 | 20k |
| R6 | 100k |
| R7 | 180k |
| R8 | 10k |
| R9 | 1M |
| R10 | 4k7 |
| R11 | 1k |
| R12 | 470k |
| R13 | 1k |
| R14 | 100k |
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