Saturday, 18 October 2014

Boss DS-1 Distortion

There's very little point in building a 1:1 clone, as you can score the original unit for peanuts as used. Possibly even cheaper than what the parts alone would cost you to build one. But instead of going through a painful bypass operation on a Boss box and having your way with the circuit, you can build your own and mod it to the perfection for yourself. There are a number of mod ideas on the web for this circuit.

The original units use Mitsubishi M5223AL SIP chip and 2SC2240 transistors. Since M5223 is still just a pretty standard dual opamp, any of our usual choices (JRC4558, TL072, NE55532, etc.) will work fine. Or in some cases, even sound way better than the original. The second transistor (the one on the top on the layout) is your first gain stage, so i do recommend socketing that one and the opamp to try out what suits you the best. The size of the board is slightly bigger than what i usually go for, but since it's 17 rows in height, this'll fit nicely in 1590B if you mount the board sideways. I built one already to see if the layout works and made a few value changes on it. 2N5088 + JRC4558 gives a mean, nearly sadistic texture for the distortion, upping certain cap values will add a ot of bass content and 5mm yellow LEDs for clippers make this one sick fuzz..



22 comments:

  1. I was just thinking I would like to build a ds 1 from scratch with the Keeley mods. Thanks!

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  2. it will be soooo much to ask about te mod? in vero?

    thanks a lot

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    1. Way too many different things, so i don't see much sense in doing 10 new layouts with each different set of mods.

      So. Check these out:
      Schematic - http://cdn.tonegeek.com/wp-content/uploads/Boss-DS-1-schematic.png
      Wampler's notes in Premier Guitar - http://www.premierguitar.com/articles/boss-ds-1-mods-1?page=2
      Pretty comprehensive list of mods - http://freestompboxes.org/members/5thumbs/Build%20Your%20Own%20DS-1%20Distortion.pdf
      (You may need to be logged in to see the FSB link)
      +m

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  3. I'd like to offer a suggestion - While I am not a fan of wampler in the least, his "18" mod and Plexi type mods for the DS-1 are far superior to the Keeley mods, and simpler to install. They can be found in the Premier Guitar article listed by Mirosol. The old style Marshall/Plexi can also be found in the book available for download at Freestompboxes, also linked to by Mirosol.

    I strongly you check them out.

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    1. This comment has been removed by the author.

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  4. Er, I meant strongly SUGGEST you check them out.

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  5. Hey Lee.Do you have a link for the Wampler "18" Mod?

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  6. I built this one! Nice sound !!

    I can only hear any difference in the distortion knob after 12 o clock.

    Is that right???

    Thank you

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    1. Did you use the correct taper potentiometer? It asks for a 100KB.

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    2. Yes, I did.

      I am using 100K lin pot.

      Have you ever built this pedal ?

      thank you

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    3. If the distortion is acting only after 12 hours, it represents about 50K ohms, right?

      What would happen if I put one potentiometer of 150K lin? Before 12 o'clock I would already be in the sound's saturation region, then the distortion would act before 12 o clock??

      Does it make sense for you ?

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    4. Well,

      I think it isn´t a problem. If you watch this video you will notice that the distortion knob do not change the sound until 12 o clock.

      https://www.youtube.com/watch?v=9ev_-DkMT_0#t=2m35s


      What do you think ?

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  7. Yeah that looks like whats happening. You could try changing the pot to a C taper (Reverse Log)

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    Replies
    1. Hello,

      I changed the 100K lin distortion pot to a 200KB.

      I strongly recommend this changed if you want a more fuzz sound close to the end of the pot rotation. I hope this information could help who wants a more aggressive distortion

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  8. This comment has been removed by the author.

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  9. May I use any other value replacement of 250pF Capacitor........???
    and
    May I use 100K/50k (lin) replacement of 20k.......???

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  10. Hello ,
    I built this layout!. but when dist &tone is 3 o, clock is very very loud and noisy.
    when I touch guitar strings sound like hum and noisy ??? is anyone build this layout ??

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  11. hmmm, build it yesterday . Sounds like a Fuzz. Nothing like the original:(
    Flabby lows and fuzz like distortion.
    I've got 13. 2n3904 and tried different combination but still the same.
    Tried 072 ICS and 4558.. its the same. Any ideas?

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  12. hi thank you ! is it possible to change the 250pf cap?

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  13. Hello!
    I have a real one. With my new guitar it lacks of volume. What if I replace the R22 on the schematic linked below with a lower value? It's next to the output.. Maybe it could help with the issue?

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    Replies
    1. Schematic: http://cdn.tonegeek.com/wp-content/uploads/Boss-DS-1-schematic.png

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