Saturday, 11 February 2012

Marshall Supa Fuzz

Made for Marshall by Sola Sound this is essentially a slightly modified Tone Bender MkII.  Fuzz Central state:

The only differences between the two: the input capacitor is 10µF instead of 5µF, the bypass capacitor on the "attack" pot is 10µF instead of 5µF, Q2's collector resistor is 47K instead of 100K, the resistor from the base of Q1 to ground is 10K instead of 100K, and the transistors are OC75 instead of OC81D. The sound of the pedals should be nearly the same, although the Supa Fuzz will probably be bassier since the input capacitor is quite a bit larger, especially with that 0.01µF from input to ground still in place, which removes even more treble.

Suggested mods

Fuzz Central suggest the following mods and the trimmer would seem like a good idea to me to accurately bias Q3:

470R changed to a 1K for more volume
8.2K changed to a 25K pot for external bias

14 comments:

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  3. It's surprising that there's been so little action on this one. This is a quick and easy build that is well worth the price of admission. I used the 1k resistor in place of the 470r and it is abundantly loud. This fuzz has sustain for days and tremendous harmonic overtones. There's a very strong midrange boost too, like a Cry Baby in a near forward position. Mick Ronson would have loved this one. Cheers, Mark!

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  4. If you find 1k means too much hiss or motor boating 810r or lower will help ,it best to socket this resister to get the right amount of volume to noise ratio to suit ,I went with 810 r , this pedal is great for Clapton s woman tone and rhythm ,

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  5. Socket the 0.01 cap as well I had a large round ceramic cap and found it to be too bright and noisy so I put a mallory 150 series cap in and its brilliant vintage sounding now.

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  6. I built this last night and kinda rejigged it so that I didn't need to twist the base and collector around on Q3.

    At first I was trying to figure out how to flip the collector and base back around, then I realized it would be much easier to instead move the emitter over to the top side of the base.

    Just move the emitter up top, replace the 100k feedback resistor with a link, then move the 100k over to the left side of the board where there's space between the caps. After that you just need a cut seperating the Q3 emitter and link from the Q2 base

    I dunno if twisting the legs really bothers anyone else much. It makes it a bit of a pain to socket transistors for me though so hope my explanation helps

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    1. Travis - that is a really good idea - and yeah, twisting the legs on these is making me a little crazy.

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  7. Can I substitute the germanium trannies for some BC108's?

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    1. Yup. It won't sound the same, but it'll definitely work. Just mind the pinout.
      +m

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  8. No it wont work with BC108 which are NPN transistors, this project is made for PNP trans, so wrong polarity

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  9. There's no sound coming out, but the LED does come on (switch works). Here are the values I got. I ordered the set (3x matched OC75) from Small Bear and it came with two resistors. The 47k was replaced with 15k and the 8K2 was replaced with 7K5. I doubt that has to do with why it's not working though.
    Power: 9.39V

    Q1
    C: 8.86V
    B: 0.03V
    E: 0V

    Q2
    C: 6.18V
    B: 0.11V
    E: 0V

    Q3
    C: 9.29V
    B: 0V
    E: 6.04V

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  10. This pedal rips so hard, it's the sound I've been chasing

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  11. Hey guys . I just bought this. Pedal and circuit looks like it's in great shape . My one issue is there is a lot of "white noise" when notes are not been played (more then normal).would love a tip to get rid of it or tame it down. Ps I also feel that the filter doesn't have a huge impact. Cheers

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