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Tuesday, July 30, 2019

Boss OD-1

This is the precursor to the SD-1 and the TS808. The OD-1 was built by Boss from 1977-1985 and made in 2 versions. Both version are very similar in circuit topology—buffer > gain/soft clipping stage > gain stage > buffer—but the early version used a quad opamp, while the later version used a dual opamp and transistors for the buffer stages. I laid out the later version a while back (and didn't know the quad version even existed at the time), but I wanted to lay the quad version out as most agree this version sounds better. Fits nicely in a 1590B. Schematic for reference.




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17 comments:

  1. kramerianJuly 30, 2019 at 12:46 PM

    Nice!
    with some mods(change value), can build jerseygirl fulltender too

    ReplyDelete
    Replies
    1. Effects LayoutsJuly 30, 2019 at 2:53 PM

      Yep. Got a PCB for that on the store if anyone's interested. It's the Odd One Out board.

      Delete
  2. naderJuly 30, 2019 at 2:23 PM

    TL074 works???

    ReplyDelete
  3. jandalesandsAugust 8, 2019 at 9:37 PM

    any substitute for 1s1588 diode?

    ReplyDelete
  4. BonansoneAugust 11, 2019 at 9:45 PM

    VERIFIED, only change the resistance from 470 to 470k (R12 in the scheme)

    ReplyDelete
    Replies
    1. BerkicauAugust 13, 2019 at 10:24 AM

      Hi mate. Which one is R12?

      Delete
    2. BerkicauAugust 13, 2019 at 10:27 AM

      Mine is working too, but the gain is farting/gated. Maybe it has something to do with changing the resistance

      Delete
    3. Effects LayoutsAugust 13, 2019 at 3:28 PM

      Thanks for catching that, Bonansone. Probably why your build sound farty, Berkicau. R12 is the resistor to the right of the 100nF cap on the right side of hte board. I've fixed the value in the image above.

      Delete
  5. FatalDizMay 31, 2021 at 1:49 PM

    This comment has been removed by the author.

    ReplyDelete
  6. FatalDizJune 3, 2021 at 12:30 PM

    Hi there,

    There is no way I could thank you so much for your excellent work! This is truely the best PCB layout site on earth. I'm a newbie on building pedals and I'm still searching a lot of stuff. Your blog has helped me so much.

    I wanted to ask you something about the BOSS OD-1, the one with the RC3403ADB IC.
    In the image above, maybe there is a mistake on the orientation and the numbering of the IC.

    I mean, according to this schematic (http://eu11.stripper.jp/pulcino/blog/images/Od-1A.gif), the orientation of the RC3402ADB on the PCB demands that the numbering starts from the upper left instead of the bottom left. As normally. I think that you counted the pin (1) from the bottom left, instead of the upper left.

    Am I right on this?
    Forgive my ignorance if I am wrong. I am still learning.

    thanks for your time and your answers.
    Jim

    ReplyDelete
    Replies
    1. Effects LayoutsJune 3, 2021 at 3:56 PM

      As the name implies, a quad op amp has 4 op amps in one package. Pins 1-3 is one, 5-7 another, 8-10 another, 12-14 another with pin 4 going to voltage and pin 11 to ground. Those op amps are basically interchangeable with in a circuit. In this case it made it easier in laying the circuit out to swap a few of them around. The functionality won't be altered because of this. Here's a pinout image of a typical quad op amp for reference.

      https://protosupplies.com/wp-content/uploads/2019/07/TL084-Block-Diagram.jpg

      Delete
    2. FatalDizJune 3, 2021 at 3:59 PM

      Really appreciate your answer and help.
      Thanks a lot!

      Delete
  7. UnknownAugust 29, 2021 at 3:29 AM

    can use IC MC3403?

    ReplyDelete
  8. ClassicFuzzSeptember 21, 2022 at 6:14 AM

    I have a question regarding this layout in comparison to the linked schematic: Why aren't the two transistors (2SK30-AY) in your layout? Are they not necessary?

    ReplyDelete
    Replies
    1. Effects LayoutsSeptember 22, 2022 at 12:39 PM

      Those are part of the original boss bypass switching. Not needed when using a mechanical bypass switch

      Delete