This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Wednesday, April 5, 2017

What the Wah?

Hadn't done a wah in a while and thought I'd do project where you can build several old school wah circuits on the same board. Many of the early wahs back in the late 60s were based on the original Thomas Organ CryBaby, and as a result many of them follow the same topology with a few value changes. Here's the schematic:


A lot of the original transistors used have a BCE pinout, so I've made 2 layouts: one for BCE and one for the more common CBE pinouts. Generally speaking your just need transistors in the 300-400 hFE range, however with many circuits, different transistors offer different flavors. So as always, socket and experiment.


8 comments:

  1. What is the value of the components? Tanks

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    1. Clink the link at the bottom of the post for the full build document.

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  2. Which is the function of d1?

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  3. I built this to the McCoy specs and I'm not getting any wah sound. Only a less loud signal. It's like the pot isn't hooked up at all. Any help would be great

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  4. hey man its a shame that this document is not verified. So my hint is:
    R3 and R7 should be connected to c5 and to the same site of L1. R3 is connected to the wrong side of the coil. its all aabout community please correct it.....

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    Replies
    1. Explain to me how it isn't already connected as you've stated: https://postimg.cc/image/q0f7t84i9/

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