Are inductor based designs the best wah?

[Keith Hilton]

Probably the most famous wah was the old Dunlop Cry Baby Wah. The Cry Baby circuit had a inductor that was somewhere between 500 and 600 mili-henrys. There were wah circuits that did not use an inductor, such as the Morley designs. I have proto-typed both types of designs. What concerns me about the large inductor on the circuit board of the Cry Baby is noise. There is a EMF field around the inductor that can easily make noise. I couldn't locate anything near the required henrys for the inductor, so I found a small transformer and used one side of it. You can figure what the henrys are by dividing what they call the AC resistance by 6.28 times the frequency. I used 60Hz frequency to figure the henrys and used a 9 volt AC wall wart in the experiment. Using the 60 Hz frequency may not of given me a true reading of the frequency of the audio signal in the circuit. Which do you like best, the inductor type wahs or the OP-Amp based wahs?

[Gino Iorfida]

If you look at the number of guitar players using wha pedals, I'd say well over 90% of them prefer the inductor based wha (whether it be a 'crybaby', a Vox, any 'original classic wha' or any of the new boutique models, they are all basically going with the old 'vox crybaby' type design with some modern tweaks.

A couple features that are a must, though:
1) most importantly, TONE
2) a buffered output when the wha is engaged, the impedance is rediculously low, and when driving a fuzz of most types, ti can reall wreck the tone (Jimi Hendrix had is buffered by Mayer)
3) true bypass or input buffer, since wha pedals will wreck the tone bypassed if not.

Extra's guys like:
1) adjustable frequency range (some guys like a deep wha, others like a shrill wha) (a 2-4 position rotary switch preferred here)
2) adjustable 'q' of the pedal (a pot works great here to get a sweet spot
3) adjustable (even with a trimpot) amount of 'drive' to the firt transistor/opamp a little bit of grittiness is sometimes wanted etc.