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.

Friday, November 7, 2014

NPN Fuzz Face

Not that the internet needs another Fuzz Face layout, but I'm adding it for the completeness of this collection. It is a DIY standard after all. This follows the stock NPN silicon version with BC108 transistors.

I've added a anti-popping pull down resistor, a power filter cap, and polarity protection diode. There a host of modifications to the circuit you can find on forums and the like, but one I highly recommend is replacing the stock B1k fuzz pot with either a C1k or B2k pot. This will give a better sweep of the range of fuzz. It's also not a bad idea to replace the 8.2k resistor with a 10k trimmer or B10k pot (wired as a variable resistor) to help bias Q2 correctly.

There are many different transistors that sound good in this circuit (I've used 2N2222 and 2N2369 trannies with good success). Just use sockets and try different ones out.



This would be a good candidate to fit in a 1590a enclosure. You could also use this layout to make the PNP germanium Fuzz Face, the ColorSound 1-Knob Fuzz, Tone Bender Mk 1.5, or the Roger Mayer Classic Fuzz. Just look up the schematics and note the component changes.

UPDATE:
I've verified the layout and put it in a 1590a using 2N5550 transistors. Here's pics of my build:




38 comments:

  1. Great layout, I did it today, and I loved.

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  2. Thanks! Glad it worked out for you.

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  3. hi, can i do the eric jhonson ff whit this pcb?it uses silicon bc183 transistors, thanks!

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    1. You should be able to, yes. Might have to get creative with the 27 ohm resistor in the EJ that goes from Fuzz 2 to the electro cap that normally goes between Fuzz 2 and Ground/Fuzz 1, and the 27p cap that goes between collector and base of Q2. Hmmm... Maybe I should make a difference layout for the EJ version. Haha

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    2. haha, ok, wait thel EJ version!

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  4. I builded this pedal with BC548 and works fine, thank for effectslayouts.blogspot.com.br!!!

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  5. Built this with BC108 transistors both very close to 260 hfe. I read 5.70v at Q2 and 1.30v at Q1 with a 6k2 resistor instead of the stock 8k2.

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  6. built this with BC108 and B1K for fuzz, No Sounds coming !
    can anybody help me out ?

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    Replies
    1. Time to debug! Double check for shorts or cold solder joints and try this out:

      http://www.diystompboxes.com/pedals/debug.html

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    2. thanks mate. will keep you updated

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  7. may i omit the b1k gain pot to fixed 1k resistor?
    if i can, how i wire it?
    because i realize i always turn the gain knob maxed out and control the gain with my gtr volume.
    cheers mite.

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    Replies
    1. You can, though it might get a bit messy on this board. Jumper the fuzz 3 pad to fuzz 2 pad and wire the 1k resistor in parallel with the 22uF cap.

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  8. ok, i will try.
    so the resistor will be across the fuzz 1 pad and 22uF cap positive side isn't it?
    sorry about my dumbness brother.

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  9. How do you guys set printer to correct settings to match the correct scale of layouts ?

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    Replies
    1. I've created scaled PDFs of every layout on the blog. All you have to do is print. Check out the Transfer Image Library tab at the top of the page.

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    2. This comment has been removed by the author.

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  10. I just built this. Sounds great except the last 5% on the fuzz knob get really nasty, splattery and high pitched. I used BC109's. Any idea's?

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    1. I had this same problem and fixed with some mods. A 100kohm resistor before the DC input and some low value capacitors in paralel with transistor legs

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    2. I had to flip the PCB around in the enclosure. I guess BC109's don't like being positioned too closely to the input jack. As soon as I flipped the pcb around and got some separation all of the excess noise stopped.

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  11. https://i.imgur.com/WPErScL.jpg
    matched 2N2222's TO18 and 10k bias pot.
    Sounds amazing

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  12. Great layout thanks! I made this and it sounds great. However it doesn't clean up smoothly using my guitar volume. It's like there's a threshold around number 8 on my guitar where it goes from being mild overdrive very quickly to full fuzz, without much gradient. There is also a bit of sputter when I first play notes. Any thoughts how I could remedy this please?

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    1. Sputtering sounds like you've got a biasing issue. You may need to play with the resistor value going to the collector of Q2.

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    2. Thanks! Noddy newbie question, but if I put a 10k trimmer in that spot, do I just connect two of the legs in and leave the third, or does the third leg need to go somewhere in the circuit?

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    3. Connect one leg to the collector of Q2 and then jumper the other 2 legs to the 330Ω/10nF junction.

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    4. I prefer, for more usable range of "biasing" and external knob, use b5k in series with a 5k1 resistor.

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    5. Thanks both for your helpful replies! A 10k trimmer has helped considerably. But |vM, you think that going over 10k might help further? If so, do you think it would be worth me whacking a 100R in series with the 10k trimmer?

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    6. If you're keeping the bias control internally, I would worry about adding a series resistor. Just up the trimmer value to 20k.

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  13. I just did this build. It works fine except I notice a very significant volume drop when the pedal is on vs. bypassed. Is this just a common fuzz face thing? I've read changing the 330r to a 1.2k will boost the output volume. Did I do something wrong?

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    1. Haven't run into that problem before. You can try increasing that resistor value, but I think something else is wrong with your build. What kind of transistors did you use?

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    2. I have the same trouble, I check the build and it's correct, I'm using bc108A. Thanks!

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    3. Try using higher gain transistors. -A variants of BC transistors are lower gain. Old school silicon Fuzz Faces used BC108C.

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    4. I removed the socket and now works better, I'll try with bc108B (I don't have the C version), other suggestion for transistor?

      I also use 10k pot instead of 8.2k resistor to bias Q2, wich is the best bias point?
      Thank You!

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    5. The B is probably good. Other options would be 2N2369, 2N5550, even 2N3904. And just adjust the trimmer till is sounds good.

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    6. 2N2907 too and 2n2222.
      The best Bias point I found was between 5k and 10k (I used b5k external pot in series with 4k7 resistor).

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  14. Hi, just giving this a go for my first DIY pedal try.
    Just a quick question, what is 4001 on the diagram?

    Thanks

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    Replies
    1. It's a 1N4001 diode and there to protect the circuit from a reverse polarity power supply

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  15. Hello guys! Please, I need a little help. I built this project with the same values components. The bypass works fine, but when the circuit is on, it just work with effect per 1 second, and no effect, and one second with the effect on, effect off, effect on. I don´t have any idea about whats possible to going on! And the effect just work with a "low notes" like at E and A strings, when I play D, G, B, and e strings, the sound is over with effect, but is ok with bypass. Someone can say me whats going on with my project? Thank you a lot, bros!!

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    Replies
    1. Check transistors pinout
      Check traces and wireds, maybe some short
      I hope it helps

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