Sometimes when a wah is true bypassed the volume seems to drop when the pedal is engaged so the input resistor can be lowered from the stock 68k down to 45k or even as low as 35k but you will get some boost if you go down to a 35k.
There is a resistor across the inductor and that can be moved all the way up to 100k from it's stock 33k.
The inductor itself can be changed out as well since the new wah inductors kinda suck by themselves. A way to deal with this too could be to get a second inductor and wire it in series with the first one. You will have to drill the pcb to accomodate the 2 inductors and possibly have to run a short jumper from one leg of each inductor. Basically, only two legs function on the inductor and the other two are actually not even wired. If you need another inductor I have them for very little $$$. I also have NOS stack of dimes inductors if you want but those will run about $20 shipped.
You can also add a 1meg resistor from the input (on the pcb) to ground (also on the pcb). This you will only notice if you put a fuzz before the wah and doesn't actually change the tone at all. Basically it is to raise the impedence of the wah input.
You also have to decide if you want your wah to act as a boost or do you want the level to remain unity gain when the pedal is kicked on. (this relates to the input resistor value as well) There is a resistor off Q1 to ground with a value of 510 ohms. By lowering this you can fatten up the tone some with a small amount of distortion added. Too low and it'll be a mess so try not to go below 300 ohms. The Color Sound wahs don't even use a resistor here so I am sure some will not aggree with the 300 ohm idea but decide for yourself. Try a 1k trim pot and adjust to your liking. Then you can either leave it as is or remove the trim pot and measure the value. Then get a resistor of that value and put it in.
There also is a cap/resistor to ground. Usually they are 100k and a 4.7 cap. The resistor sometimes needs to be lowered to 82k and the cap raised to something higher but not more than a 10uf. Pay attention to polarity of the cap when you remove the 4.7uf as the new cap will need to be put in the same way.
There are 2 .01 caps in the circuit. One is the input cap and the other goes to Q2. Raising the one going to Q2 to about a .033 is kinda cool but shifts the frequency point at which the wah sweeps. This is also the cap to change to make a wah into a bass wah. Perhaps the .033 will be too much but fun to mess with none the less.
The input .01 cap is also good to replace. Try a .047 or even a .1 as this lets more signal through. I often find the stock .01 thins the sound but alas this the value that all wahs come with none the less.
Good luck and feel free to email me if you have any questions. My email address is Wahmods@PedalworX.com
Happy New Year!
Regards,
George
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