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Wah mod for variable Q?

12/20/2002 12:31 PM
Joe D
Wah mod for variable Q?
Are the mods out there for this?  
Do I want to do it?  
12/21/2002 12:55 AM

If yours is the crybaby style wah, there is a resistor across the inductor. Varying the value of this resistor varies the Q (if i remember correctly)  
You'll have to tell us what pedal you want to mod.  
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12/21/2002 2:07 PM
Joe D

It's the GCB-95.  
Sounds like it's just 4 more resistors & a 5 way rotary to me.
12/21/2002 8:20 PM

"Sounds like it's just 4 more resistors & a 5 way rotary to me."
Better idea: ONE 100k pot. Take out the 33k resistor between the leads on the inductor and wire up the pot as a variable resistor. I drilled a hole and mounted mine on the side of the pedal. I usually keep it right about halfway, but it's nice to be able to tweek it if I want to.  
Another useful mod would be to vary center/resonant frequency. A variable capacitor (two parallel caps with one in series with a variable resistor) in place of the cap in the feedback loop between the emitter of Q2 and the base of Q1 would work nicely. Don't understand why anyone would prefer a rotary with presets and all those extra parts to a continuously variable pot.  
One more thing; increasing the input cap (in the range of x2 to x5) of course would let more bass in.
12/25/2002 10:33 AM
Alex D.
Have you seen this page?-
12/27/2002 7:07 PM
Joe D

Sure have.  
Tried a few of the mods there & put it back.  
Just wanted to give something a try. I really like my wah, just bored. :)
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