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passive wah?

10/4/2002 3:14 PM
Mike Cornett
passive wah?
Hello folks,  
I was curious to know if a Wah could be made in the style of a volume pedal??? (Meaning no power running in it). The rocked forward position would be the natural tone, rocked back would be the lowest tonal adjustments like in the typical wah where rocked forward is a lot more nasally, and high pitch.  
I realize without the 'noise', it wouldn't have the same whiney wah characteristics we all know of, but that's not really my point in this...I want a silent working volume/tone pedal. Not sure of what pot value I'd use yet, but that's up for testing.  
Anyone know if such a pedal could work?
10/4/2002 5:05 PM
jakob Erland

For a Wah effect you'll need a high "Q" bandpass or lowpass filter. The high q's can't be made passively unless you have a VERY low output impedance from the previous stage. Like a speaker output or something.  
But for a guitar to work with it directly, you'll need an active design.  
Best regards,  
Jakob Erland  
Gyraf Audio
10/4/2002 9:52 PM
Mike Cornett

No possible way of manipulating the turning of the 'tone knob' on my guitar via footpedal? (other than wiring my guitar straight to a pedal of course).  
Could I some how split the pickup to tone pot signal for bypass capabilities in the guitar, so one selection works the guitar's tone pots, and the other selection works a footpedal's tone pots, via some sort of other input?
10/4/2002 11:11 PM
Mike Cornett

I read on geofex about an expression pedal for use with an existing stomp box....  
Instead of having to drill holes in the guitar, etc...  
I wonder if this triple octave/ volume+tone pedal combo could work if they were just hooked up to eachother via the 1/8 input/output cable that the guy from Geofex recommended??
10/4/2002 11:18 PM
Sean K
It might not be a wah but a pedal tone could be interesting,mild,but interesting.What you could is use a twin ganged 1M linear pot and use one side with a 250k resistor accross it as a tone and the other with sgnal in and earth,actually you'd need three pots,the tone,and two cross wired to create a phase change.But it'd be passive so its all about signal loss so maybe a compressor in the chain wouldn't hurt.
10/4/2002 11:43 PM
Mike Cornett

Would this effect the natural tone of the guitar? My goal would be to have it not effecting the tone....or realistically I should say as little as possible, as with the Volume Pedal i use.
10/6/2002 8:59 AM
Sean K
Yes it would affect the tone,usually by losing highs,so maybe it wouldn't affect tone so much as lose it.You might bypass the whole lot with a 1 nano or 500 pico and just play with the mids on down which are always stronger current wise.The nature of something like this is that you'll be learning and thats never a bad thing...

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