Saturday 9 July 2016

Smallsound/Bigsound Mini Overdrive

A "Mini" version of Smallsound/Bigsound Fuck Overdrive.
Thanks to Brian for uploading his original schematic!
(You can find original thread and schematic here.)

11/07/16 Layout updated!
Brian has suggested to use J201 for Q2 & Q4 and to add a 10K trimpot between V+ and the Bias pot.


36 comments:

  1. Great looking layout Alex! Can't wait to build this one

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  2. Sorry Alex didn't see your version. Just verified Anders version in unverified though. Really nice OD!

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    1. No problem!
      Just seen Anders layout.
      Glad it works!

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    2. Fantastic! Have owned one since they first came out - am still building another! This is one of those pedals that sounds equally good on bass and guitar. Thanks

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  3. Too good! I really love the sounds you're getting with the baritone guitar as well.

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  4. a few small notes from here from the builder (myself) -
    i personally use J201 for the first and third stage JFETs and 2N5457 for the second stage. a small note about the main BIAS knob - there should be a 10k trimpot between it and V+ to help fine-tune the range.

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  5. Thanks for all the help, Brian!
    I've updated the layout.

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  6. There needs to be a new Good Guy Brian meme. He's a class act, through and through! Any interactions I've had or witnessed (online) with he and SSBS have been thoughtful and helpful. You rock, Brian - thank you!

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  7. Thank you for this awesome layout. You can tag it as verified. Just a question, if I understood correctly the 10K trimpot is here to set the range of the bias pot. If so do you have some advice on this range (if not I will make some try but I'm interested with your opinion).

    Pics of my build :

    http://dl.dropboxusercontent.com/u/9520625/20160718_145823.jpg

    http://dl.dropboxusercontent.com/u/9520625/20160718_145836.jpg

    Thanks again

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    1. Thanks Thomas!
      You are correct about the trimpot.
      I don't know how Brian has set it on the original pedal but you should really test it and find the spot that gives the best range based on your taste.

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  8. I would probably set the bias pot to noon and tweak the trimmer to the best spot, that way the best setting is at noon and you can adjust the bias up or down from there

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  9. Thanks for the advice. I tried noon (2 to 7V), the lowest possible (like that the range is almost 0 to 5V), the highest (4V to 9V). I prefer the highest. With very high voltage and low gain there is some awesome clean sound (to my taste) and when you roll down to 5V you have some awesome gain sound. That's my favorite range.
    Thanks again for the layout and advices

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  10. you can easily set the range of the bias pot by ear - turn bias, bass and gain to minimum then tweak the bias trim until you get some crackly/cruddy signal passing through, then tweak just past that. when you crank the bass, you should get farty/boomy sounds on the lowest bias setting.

    noon-ish on bias will then give you the fullest, most gainy setting and the maximum setting will be clean-ish with a little more headroom.

    that being said, do what you want for yourself to find the most useful and interesting thing like thomas roman did. *thumbs up!*

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    1. this is brian from smallsound/bigsound in case that wasn't obvious.

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  11. Thank you Brian, for this great creation and for the advices. I will try your way to set it.

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    1. sounds like your noon (2-7V) is probably fairly close to where i set it perhaps.

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  12. I tried Brian's way to set it and it was very interesting, that was the way to have the wider sounding option. But I came back to an higher bias (3,2 to 8,4 exactly). I love the extra headroom that high bias give on low gain setting. It's really one f the best overdrive I know. Thanks again Brian.
    Before this post, I didn't know SS-BS. I take a look on your website and I'm very interested by your fuzz. I take a look but there is nowhere in France where I found SS-BS. Can you point me to shop or do you sell pedal only on your website?

    Some thing I forget. Bias pot was reversed for me (higher level of bias CCW). I just attach 1 and 2 instead of 2 and 3 and it correct it.

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    1. to each his own of course! i was thinking a lot about the splatty, lo-fi sounds when i designed it and you get much less of them with the bias shifted closer to 9V. whatever! as for my pedals, i have retailers in the EU (found under the "where to buy") tab on my site and i ship internationally if you prefer to buy direct.

      yeah bias pot may have been a mistake on my part in labeling.

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  13. Thanks to Alex for the fantastic layout, and thanks to Brian for releasing his design and being so damn awesome.

    I put two of these in one box, running in series. Sounded so good, but I found the top end to be just a tiny bit too fizzy for my tastes, so I ended up adding about 170pf off one of the J201s and that made this thing absolutely perfect for my ears. Also allowed me to crank the treble up more, if needed, without adding more fizz.

    Thanks again!

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    1. Hi! I want to try your little modification. Where did you solder the 170pF capacitor?

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    2. I found that replacing the 15nF top left of the layout with a 22 or 27nF cap helped reduce the brightness peak in mine. It feels a little more solid to me now - but that's probably just my ears and my rig. This is a great pedal and as soon as I have the $$ I will buy one from the maker. It's that cool.

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  14. I was looking at the product description on the SS/BS site and the gain pot controls two separate stages. Think it'd be worth splitting it into two separate controls?

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  16. Here's a checked over schematic, previous one was erroneous lol.

    http://imgur.com/ZqAHaI3

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  17. I don't have any 5457's, would a 5458 be ok?

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  19. So would gain 4,5 and 6 be lugs 1b,2b and 3b on one half of the dual pot? I just finished this up and the gain unless the gain is at 12:00 I get no sound from 12-00 on it behaves normally. Any thoughts.

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  20. Fixed it shortly after that post but forgot to update it. Misplaced component. I can't get that octave fuzz tone, maybe it's due to my biasing but sounds great otherwise. I'm also using a B100k dual for the drive control and it seems much more usable. I'm thinking of swapping the bias pot for a linear taper as well.

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  22. Any chance the f@ck Overdrive layout will get posted, or is it a straightforward mod of this one?

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  23. No chance without a schematic, unfortunately.

    If it's financially possible, I highly recommend buying one directly from Brian. It is a truly great pedal, worth every penny and more, and Brian is one of the best builders out there that you could support

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  24. Just built one of these - great pedal! I didn't have a dual 100KA pot so used a dual 250KA and it still works. :-) I don't go anywhere near full gain, so do you think it matters? Should I get myself a dual 100KA pot?

    Now I'm off to check out Small Sound/Big Sound's website. Good stuff.

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    1. Looking at the schematic posted on 12 August 2016 (see above), the 250KA pot will work just fine. At minimum gain settings, your pedal will be a tiny bit quieter than stock.

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  25. Hi! I just built this and it only works in full gain. The volume drops very fast and at around eight (of ten, not o'clock) it's completely quiet, maybe some small crackle. Anyone have any ideas of what might be wrong?

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  26. I've just built this - and there seems to be a discrepancy between the two pictures - the right hand one one shows a cut underneath R$ (the 1K resistor below the bias trimpot) - the other doesn't. I've just done it without and there doesn't seem to be much control over the sound of the board using the controls. I guess it will work better with that track cut?

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  27. Shouldn't the gain pot be a 100kB dual not A? That's what is says on the schematic and other stripboard layouts I've seen. Plus linear is much more common for gain, not log right?

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