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, March 25, 2016

Zvex Fat Fuzz Factory

For Fuzz Friday, here's a layout for the Fat Fuzz Factory in a 1590B in a more traditional orientation. All pots are board mounted as well as the Fat Switch. For C1 and C2 you'll probably want to experiment with values. Using an on/off/on switch gives you an extra option over the original. 3.3uF is a good place to start with one of them. Just a note, whatever value you chose will be in parallel with the existing 100nF cap. Thanks to p0mp0 for sending in his layout.


19 comments:

  1. you have wrong at gate, comp and stab pots.
    GATE: 1st and 2nd legs are contecting with GND and 3th leg connect with 470ohm.
    COMP: 1st and 2nd legs are contecting with 47k and Emmiter of Q3 and 3th leg connect with stab pot 3th leg.
    STAB: 1st and 2nd legs are contecting with 9V dc and 3th leg connect with the remaining circuit.

    ReplyDelete
    Replies
    1. There seems to be differences between the various schematic on the net and either way will work. This layout follows this schematic (which I trust):

      http://basicaudio.net/Fuzz%20factory%20schem.PNG

      Delete
    2. Ιn both cases it will work properly but the pots will operate reverse!

      http://cdn.toptenreviews.com/rev/scrn/medium/54098-inventobox7.jpg
      This schematic is from vxter Inventobox then contain fuzz factory, if we take the case of Volume pot that the 1st leg is connect with GND then we conclude 3 leg of pot connect at square shape on pcb... with this logic out the other connection of pots!!!

      Delete
  2. For the man with "Ample taste"!

    ReplyDelete
  3. what is the real value of c1 and c2 in the official fat fuzz factory?
    For Q2 and Q3 , AC128 or AC122?
    thanks a lot

    ReplyDelete
    Replies
    1. I don't remember off the top of my head. Use sockets and experiment. Zvex has used several different transistors for Q2-3. AC122, 125, 128 should all work. Again, socket and experiment with PNP germaniums.

      Delete
  4. O.k. it works... Crazy(!!!) Fuzz. it's a bit wierd though, the volume of this thing is monstrous, i get to 9 on the knob and its WAY more than unity. maybe there is something wrong with my build?

    also, if you use Taydas pots (with dust covers) either take off the covers or spae out the holes (with the drilling template). I found that using so many onboard pots is very tricky...

    ReplyDelete
  5. Oh, and the switch doesn't seem to do anything. I've put all sorts of caps from 3.3uF to 100uF, no change in signal... :(

    ReplyDelete
  6. And dimensions for PCB printing? anybody knows please? :)

    ReplyDelete
    Replies
    1. There are PDFs pre-scaled and with the dimensions for all layouts in the Transfer Image Library tab at the top of the page.

      Delete
  7. Hi. Do you have a drilling template for horizontal orientation? Do you know if it fits in a 1590b with 15mm sized pots? Thanks.

    ReplyDelete
    Replies
    1. Assuming you wire the majority of the pots offboard it should fit fine horizontally. Don't have a drilling template for it that way though. The other Fuzz Factory layout fits ok in a 1590b and it's designed for the controls to be laid out like the original.

      Delete
  8. Anyone verify this one?
    I'm between this and the standard FF: I want to use 1590B and omit the spdt switch

    ReplyDelete
  9. I'm new to electronics, so maybe my question could be stupid. The Fat Fuzz is nothing but a Fuzz Factory with a switch right? so how could Fat FF not work if the FF is working? there's nothing different but a 1M resistor, what's its function? thank you a lot! this site is really great!

    ReplyDelete
  10. oh yes, I've build this one over half a year ago and it works quite similar to a vexter fuzz factory. Only change i've made is using AC132's. It does oscillate great in the low end as well as high end. Only two things that I would like to change but didn't manage to sort out yet. Being that it's a very bright sounding fuzz, using it on my bass I loose a lot of low end. The other thing is that despite socketing I never found the right values for the capacitors on the switch. I barely hear a difference when it's not oscillating. It's not as fat as I hoped it to be but unlike many other pedals that aren't suited for bass this one gets toyed around with lot's of times.
    Verified!

    ReplyDelete
  11. thank jay for verifying! I built it and it works great! I used ac128 and for caps I put 10nf instead of 100nf and then 100nf and 1uf on the others, the difference is noticeable and I find it fat enough on my guitar. thanks guys!

    ReplyDelete
  12. can i build it with silicon pnp's instead?

    ReplyDelete
    Replies
    1. You could, though you'd need to modify the biasing. It's not just going to work if you throw in silicon transistors. It's designed for low hFE germaniums.

      Delete
  13. when i turn the volume all the way down on my guitar i hear a lot of noise, is it normal? when the gate or comp knobs are up it doesn't do it. y used matsushitas b175 for transistors.

    ReplyDelete