This is a rather interesting looking fuzz – one that I had overlooked until someone pointed it out to me (thank you Mister Hate). Before this, I was only aware of the MKIII-style fuzz that Sola Sound made for Carlsbro.
Despite having three transistors and being made in the mid-sixties in the UK, it is in no way related to a Tone Bender / the Maestro Fuzz-tone.
History: Link to Fuzzboxes (excellent site by the way)
Discussion: Link to FSB
CARLSBRO FUZZ-TONE | POINT-TO-POINT LAYOUT
So this is based on the original, with a few minor changes regarding placement. The layout on Freestompboxes did get me started, so credit to all those involved.
The original board is quite a mess (check the photos on fuzzboxes.org), which is why the transistors aren’t shown. The transistors sit above the resistors and capacitors on the board.
ORIGINAL SCHEMATIC FOR THE FUZZ-TONE
I redrew it, as the original was making my brain hurt.
This kicks out a pretty mean-looking wave – I’ll attach some actual scope traces a bit later.
It looks like it has a focussed mid-range
MODS FROM THE BREADBOARD
Jumper / remove the 100k resistor on the input
Remove 220k on output
Move attack pot 2 to V-
Increase input and output caps