I've found this diagram and decided to bring it to life. Unfortunately it didn't work. By the way I am not sure if my 100k ohms resistor works properly.
So the question is that is the diagram correct or do I need to add something on it ? or is it resistors failure or mine ?
Its a classic Fuzz box, with diode clipping the output, your 100k pot is just a volume control for your guitar amplifier, its possible the 100k pot is too high, try a 10k pot.
It cant change my tone, but it reduces volume. I am not sure if variable resistor works properly tho, I checked the scheme 1000 times and it's OK. Also the page said that not every circuit is correct and some of them need to add something so I decided to ask the question here. Just it does not do it's job.
The 100k pot at the output just controls the volume, it wont alter the tone, if you want to alter the tone you need to adjust the filter RC's on the op amp output 10k,1nF.