Corduroy Fuzz (Wampler Velvet Fuzz) mods

[harmaes]

I've build the Corduroy fuzz for the 2nd time and after a succesfull build with a working brightness pot (wasn't working in the first build) I found the pedal too dark and replaced the 25k bright(ness) pot with a 50k pot.
This was tedious and hard to remove and somehow the 50k pot doesn't seem to do anything tone/brightness wise anymore. I checked if the pot worked and all connections were still intact which was the case. So looking at the 50k pot it reduces the corner frequency to 250hz or something? The advantage of the 50k pot is that it makes the pedal brighter so a working pot is not a necessity but I'm a bit flabbergasted why I keep having issues with this brightness pot?!

I build around 40 pedals with veroboard and PCBs and have always been able to fix broken parts of build mistakes. So in general I want to find out why this pot isn't working anymore and also what mod options there are related to increasing the brightness of the fuzz?

Here are some threads already discussing this:

Brian Wampler: https://www.thegearpage.net/board/i...vet-love-it-or-leave-it.1489711/post-18858881

Corduroy too muddy on Big settings

Is there a way to fix the muddiness of this pedal? I've checked the circuit around the 2n5089 transistor. All my values are correct. J201 is also dialed-in on the Tight side but when I switch to Big, everything is just too muddy. Is there too much bass going into this circuit? transistor...

forum.pedalpcb.com

https://forum.pedalpcb.com/threads/muddy-corduroy.1547/ with a good explanation of the different tone related options in this pedal by @Chuck D. Bones .

I would love to be able to better understand how to interpret circuit parts and specific tone (stack) related mods/options. Anywhere to read up on this (videos, online articles, books) and how to best learn and approach this?

For me I think I'll try to go back to the 25k pot (hopefully everything stays intact) and socket the caps C18 and C19 to experiment with lower values or removing C18.

 

[harmaes]

I experimented with C18 and C19 in the circuit, removing them and reducing values of C19 and IMO there's just a very tiny amount of brightness improvement. I had C19 on a switch with 10n, 5k6n and not in the circuit and it only was marginally different. Removing C18 IMO introduces some more chance of oscillation.

To me the 50kB brightness pot instead of the 25kB offers the best improvement. I always have this pot on max so it can even be replaced with a fixed resistor of 50k.

The big setting cleans up better with the volume knob then the tight setting and reducing the neck pickup (single coil and HB) that way to 2 or 3 on the volume gives a nice clean edge of breakup sound on the big setting.

 

[hamerfan]

I don‘t think c18 or c19 are not the problem. C5 and also c10 are too big IMO, shunting a lot of highs to ground. My recommendation would be 22nF and 2.2nF