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Someone help! DIY wah wah guitar effect Answered

Instructables community, I am 13, just learning to play guitar, and want some awesome effects to spice up my sound. I have seen the kits for DIY wah wah effects and wish to make one. I don't plan on etching my own circuit board, and i don't want to buy one. All of the schematics are pretty complicated and i have no idea how to decipher them. I will probably end up using a protoboard; but can someone simplify the plans and/or give me the links to the parts i need? Thanks in advance, -Nick



9 years ago

Building DIY guitar FX is wicked fun, congrads on trying it...

Regarding Wah pedal circuits: The standard wah is usually a variation on the classic Vox Clyde McCoy pedal. The circuit itself isn't very complicated, but read on...

There are problems with DIY wah pedals, especially if you're building completely from scratch (and don't want to spend much):

-- The pedal itself is difficult to fabricate (most DIYers buy a used, non-working pedal to start with.)

-- The POT used in wahs is usually a custom taper, and almost always a sealed POT. Translation: expect to pay $20-30 just for the POT. If you're starting with a broken pedal, its POT might be usable...

-- The classic design requires an inductor, value of approx 500mH (milliHenries.) Common types are Fasel and Halo. One of these will cost $15-$30. There are alternatives: such as using a small audio output transformer for the inductor. See this article for details (it's got more info than you need.)

The upshot is that wah pedals are more an intermediate project, simply because of the cost and fabrication skills needed... compared to a simple fuzz or booster, anyway.

Thanks for the reply. What would be the easiest one to make to start out with? And, where could i find a broken pedal to fix up?

Except for the pedal mechanicals (and finding the correct inductor) the circuit of the Vox wah is simple--only two transistors and a few discrete components(both the links I gave above show variations of the same type of wah.) You'll find PCB boards and wiring info online if you look...

RE: the pedal itself-- search ebay for something like "wah repair" or "wah project".

There's another option, too: the expression pedal from an organ. Although they don't have nice enclosures like guitar pedals, they should have both a working pedal and a sealed POT. Try searching ebay for "organ pedal" (I see one now available for a total of $16, although it ends in only two hours...)

For an inductor, google or search ebay for "wah inductor", plenty should show up... The "tech" link I posted above has some other inductor ideas...read the Building a Wah from Scratch section.

He also mentions some inductor-less wah circuits, but the classic type that use an LCR filter (L = inductance, C = capacitance, R = resistance) requires an inductor in the circuit... They are the most popular for a reason: inductor exhibit resonance, which is why wah-wahs sound like the do...

Inductor-less wahs aren't very common because they don't sound as good (personal opinion, shared by many)...but they do sound different from most wahs, so the occasional commercial version is available.

This stuff still seems a little complicated to me. I can't find a cheap broken crybaby wah or a cheap organ pedal anywhere right now. I might post some stuff on craigslist in a little bit.

What would be the simplest thing that i could make that would achieve a good effect?

I'd go with a booster or a fuzzbox...

Something like the "multi-face" or the "Sili-face" on runoffgroove, both based on the "fuzz-face" (60s fuzzbox.)

Or Craig Anderton's Tube Sound Fuzz (I built one years ago and it sounds cool.) Here's a nice PDF with diagrams and schematic. This design uses a CMOS 4049 hex inverter chip for the guts--it's easy to find online.

I just spent the last 20 minutes going through pages on wikipedia aboutt guitar effects.... :(

Waaah Wahhh Whaaaamyyyyy!!!!

P.S. If you're going to help, can you find a link for a site that sells (at least semi-) cheap electronics? I don't want to give radioshack any more money than i need to.