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, February 4, 2015

EHX Big Muff - Triangle

I know, this is the 3rd different BMP layout I've done, but this is the one I'm the most happy with. It will easily fit in a 1590B, it has board mounted pots, and said pots aren't all in one row across the top. As with the other Big Muff layouts, you can build pretty much any version on this layout (just refer to the schematics), but the components listed here are for the '72 Triangle version. For the board-mounted pots, I drew this layout with these kind of pots in mind mounted on the solder-side of the board.


18 comments:

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    1. Yep. Anything that's been verified will have the "Verified" tag at the bottom of the post.

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  2. Hey man, really digging your layouts, they are awesome!
    Anyways, I finished doing this one and I followed every step of the layout/schematic and everything, but i used BC547B transistors instead of the 2N5089 or the MPSA18 or the BC550C, because I couldn't find any on my country (or at least in my city) and I noticed the pedal has REALLY low gain, could that be the effect of the transistors? Should I change them?
    That's all, thank you, and again: your layouts are great!

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    1. The BC547B is a lower gain transistor so it might be the culprit in this case. If you can find the BC547C you should have better luck. Really, just about any transistor with a gain higher than ~300hFE should work fine. I've built several BMPs with 2N3904s with 350hFE and they all sound great.

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  3. After two builds I finally got this one working. I like alot. It's a keeper!

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  5. Hey, I could use transistor 2N3904G?

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  6. Hello, how can i adds a mids switch (like vicks audio's rams head) to this circuit? Thanks a lot men.

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    1. You can put a DPDT on/off/on in parallel with the 3.9nF cap. On one side put a 4.7nF cap, and the other put a 10nF cap. This will give you stocked scooped mids in the middle, flat mids one way, and boosted mids the other. Check out the switch wiring in this vero layout:

      https://4.bp.blogspot.com/-b3sslVExvqU/VN5E9fHwkHI/AAAAAAAADyE/oJyEfLMJLic/s1600/BMP%2B-%2BTriangle.png

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  7. I've tried to replicate this layout with Ram's Head components and I'm getting very weird issues with the tone control. At the extreme ends of the pot (max treble or max bass) I get a loud clear signal, but in the middle tone positions I love volume and get a very poor signal coming through. It almost sounds like a poorly biased transistor. Does this sound familiar with anyone or does anybody have suggestions? I've checked the pots and troubleshot the caps/resistors in the tone circuit with no luck.

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    1. *in the middle tone positions I lose volume

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  8. Might be late to the party but I believe the Q1 transistor is labeled incorrectly.

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  9. I'm new to building pedals, I'm having trouble wiring my LED where should I solder the LED connection from the PCB. Thank you!

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  10. how do i wire the mids switch?thank you for your help!

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