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, July 17, 2015

Sam Ash Fuzz-Stainer

The Fuzz-Stainer is a pretty rare fuzz box made by Sam Ash in the 70s. Don't confuse this with the Sam Ash Fuzzz Boxx/AstroTone, as it's a different circuit. Original units used 2N5173 transistors with BCE pinouts. I've made 2 versions of the layout, one for BCE transistors (on the right) and one for CBE (on the left). 2N2222s or 2N3904s seem like they might be good substitutes. Output is pretty close to unity with the Volume pot maxed, so you may want to replace the 10k pot with a 50k or 100k, and/or reduce or remove the 68k resistor from Volume 2 to Out. To make the trimmer external (like the Jerms clone in the video below), use a B20k pot with lug 3 going to the emitter of Q2, and lugs 1 and 2 going to ground.




3 comments:

  1. Hi,
    really nice layouts. Thanks

    One question,
    didn't the original units used 2N5172 and not 2N5173?

    You can clearly see the 2N5172 markings in the pictures of an original unit in this links:
    http://tonemachines.blogspot.pt/2012/02/sam-ash-fuzz-stainer-197.html
    http://2.bp.blogspot.com/-Vcm_cGa7Mhg/Tz6Jos4v0yI/AAAAAAAABDQ/RhcURVrL0iE/s1600/IMG_0330.JPG

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  2. Verified.
    Used the EBC layout and 2N2222 transistors.
    I used an off-board 25k pot instead of the trimmer. With the pot set to 3.3k, I measured about half voltage on q2's collector and it's around there that you get the best guitar volume clean-up. Adjusting the bias from there can get you more gated, splatty sounds.
    Not much volume stock, so the smaller output resistor and/or larger pot are good ideas.
    Overall, it's buzzy-sounding and has pretty good clarity with chords.

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