Saturday, 6 February 2016

ZVEX Fuzzolo

   This cool sounding fuzz was traced by our very own Ciaran Haslett in the forum. Check the forum for Ciaran's schematic, info, and layout (which is one column smaller than mine). I noticed Ciaran requested that this be redrawn for the main site, here you go :)






38 comments:

  1. ahh. mosfet pinout and an extra cut snuck under that cap. see anything else?

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    1. Nope :) But the tweaked pinout is not correct for BS170. As it is - it'll need the gate/source pins twisted. With cut removed and twisted MOSFET pins this is verified. Altough, these FETs are quite delicate devices and thus, i wouldn't recommend twisting the pins.
      +m

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  2. All I changed was:

    Flipping gate and source labels - surrounding components didn't move

    Removing the extra link

    I'm not sure what you mean about twisting the legs on the BS170 though, unless yours have a different pinout then mine

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    1. Looks right here x.x

      https://www.fairchildsemi.com/datasheets/BS/BS170.pdf

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    2. Maybe one of you has a 2N7000?

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    3. This comment has been removed by the author.

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    4. My bad about the pinout. Strike that.

      But. There is one more error that made me question myself and the pinout. Once that is fixed, then it's verified.
      +m

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    5. Yup. Now that the 3k9 is where it's supposed to be - you can tag it.
      +m

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    6. Looks like drawing layouts first thing in the morning ain't working out too well for me :O

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    7. Nah :) Don't worry about it. I've had my share of erroneous layouts.
      +m

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    8. Also, check your mail :)
      +m

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  3. I mean removing extra cut, not link

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  4. I made this from Ciarans layout a few weeks ago. It sounds great and is really loud. I much prefer it to my woolly mammoth.

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  5. This comment has been removed by the author.

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  6. Haha...excellent Travis. Cheers for the mention. Top job as always! ....and gone is the number 19!!!

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  7. I can verify Ciarans layout. I also used a 2n7000 instead of a bs170 and it sounded fine to me. Just make sure you flip it 180 (different pin out)

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  8. Works fine, really good fuzz!

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  9. I built this a few weeks ago with the previous layout and had osscilation a through most of the PW sweep. Doesn't this layout have any issues?

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  10. What's with the switch? Does it exist in the original?

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    1. it's a mod ciaran did for active or passive pickups

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    2. Thanks. Which one is for passive?

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    3. The original has an internal jumper to switch between the 39K (labelled Active) and 750Ω (labelled Passive). The switch here is just a handy way for us DIYers to select between the two.

      If you want passive only...

      Remove the switch and wires
      Connect your Input wire to where is says SW3
      You can also remove the 39K and the cut beside it

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    4. There is very little difference with 39K/750R when using passive pickups. Tried the stock values on a switch first, but dropped it for fixed 680R. Again - very little impact in the tone.

      This is definitely the wrong place for the following comment/discussion - but who in the world would ever want to use active pickups? It's 1:1 with having a sucky booster circuit in front of your pedalboard at all times. It may work for metalheads who have one tone - EMG 81 to Peavey 6505+ with gain maxed (as you can't even think about using the "clean" channel as it's clipping in way that just yells "broken!"). If i want a booster circuit before the rest of my board, i'd want to see a few options.. But then again. It's just me.
      +m

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  11. LOL we pretty much share the same opinion on active pickups. Personally I was planning on just running my input directly to the 750Ω bypassing the switch altogether

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  12. Is the volume pot log or linear? And what should I do with PW1? Thanks for making this layout!

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    1. Audio is Log.
      Pw1 is not connected (or you could connect it to Pw2).

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  13. Silly question... what is "SW" on this layout?? Thanks!

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  14. out of 2n3904s, but i do have :

    2n2222
    2n4401
    2n5088

    mpsa13, lol jk

    and i got 3 bc108bs, they all tested from 320-350 hfe. If i remember correctly last 3904s i tested seemed like right in same range. They are tin can versions...

    2n2222 and 4401 were like in 200s, 5088s in 500 range. Or the 5k hfe mpsa13 that just turns my multimeter off lol. I dont hae any sockets and got a week before can place a new order. Thanks for any replies

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  15. out of 2n3904s, but i do have :

    2n2222
    2n4401
    2n5088

    mpsa13, lol jk

    and i got 3 bc108bs, they all tested from 320-350 hfe. If i remember correctly last 3904s i tested seemed like right in same range. They are tin can versions...

    2n2222 and 4401 were like in 200s, 5088s in 500 range. Or the 5k hfe mpsa13 that just turns my multimeter off lol. I dont hae any sockets and got a week before can place a new order. Thanks for any replies

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    1. 3904s are usually in range of 250-350 hFE, so you are golden with any of those. Go with BC108Cs and mind the pinout.

      I'd also recommend leaving the input switch out. Just take the input to SW3. The switch does very little to the tone of this circuit.
      +m

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  16. Breadboard it or wait until you're ready to build it

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  17. The last gain stage arround the BS170 is a SHO. Is the 51k resistor right? The SHO has a 5k1 on this position.

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  18. If it helps others... I changed input cap to 0.1 for a tighter bass response (I'm just using it for guitar) I also put a 1k trimmer between the positive of the top 100uF cap and where it's socketed. This works as a traditional fuzz pot, if you're wanting to tame the fuzz a little.

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    1. I'll try this. Mine still doesn't sound as in the demo and I can't find any errors in my build.

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    2. Alas this shouldn't fix anything if it doesn't slund like the demo already. I used the layout posted in the forum. I also built it twice and i have no idea what i did wrong the first time. Have you checked all the usual things like solder joining two strips together?

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