Tuesday, 4 March 2014

Demeter Fuzzulator

This design was pretty awkward to get down to a reasonable size due to two opamps, a trimmer and mere ten diodes on board. I'm not liking the asymmetry, but i still fitted it in a quite compact size. In the demos, this one sounds like a nice and creamy opamp fuzz..

From Demeter site "The Fuzzulator was designed to be a fuzz with focus. So many fuzzes sound cool but get lost in the mix because they don't have a clear sound image. I solved that problem with tonal pre emphasis before the sound hits the distortion generator. The unit also has both LED or germanium diode distortion available at the flip of a switch." - James


23 comments:

  1. Built it. Works and sounds very good. Fat, creamy, defined and loud. The trimmer sets how high signal gets fed to the the TL061, so one can get more overall level by turning it clockwise. Original units apparently have it set dead center, which boosts enough as it is. Not going to bother, but if i build another, i'm probably going to use 20K or even 50K lin pot for volume. That should result in better feel of the pot. Not that there's anything too badly wrong with the log though. Only downside is the switch. The difference between the modes isn't that big, but still noticeable.

    Very nice opamp fuzz indeed.
    +m

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  2. This is awesome, Mirosol.Have wanted this one ever since hearing Jack Zucker's demo a while back. Just placed an order to Mouser for the LF442 - the only part I don't have on hand for this. At least I can get the rest done and then just plug in the IC...

    Thanks man!!!!

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    1. I think you could get away with TL072 or JRC4558. Or basically any dual opamp. solder a socket for it and try a couple different ones out. I used sockets on my board, but didn't test any other chips yet.
      +m

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    2. Will do. Wasn't sure if the others could be subbed because I saw that it was referred to as a "dual low power Jfet" in the description at Mouser. I do always use sockets for ICs and Trannies. Not only for fear of burning them up, but it's also cool swapping around for more sonic options....

      Thanks again

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    3. I too did not have a LF442, and tried JRC4558, TL072, N5532, and LM1458. ALL exhibited significant fizzle in the last 20-30% of the Fuzz pot rotation.
      Tried a OPA2134, schazaam!
      I am assuming that the LED's are always on and SW1 brings in the array of 4148 and 34's.
      Any reason why D1 is not a 4001 or 5817, just curious.
      As Always, thank you for the layout.
      And now onto to #3 in the series the Fat/Flatulator.

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    4. Flatulator :P

      About the LEDs, you're correct. About the polarity protection - This time the schematic states 1N4148 as series polarity protection, so i went with that. That will drop the voltage more than 5817, so there's a chance it is 4148 on purpose.
      +m

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    5. The 1N4001 and 1N5817 can both handle more current but with most of these effects there'd be no problem using a 1N4148 for reverse polarity protection.

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  3. I built this one yesterday and I love it. on mine there's a huge difference with the loose/tight switch. thanks for posting it. pics below:

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/Fuzzulator/FUZ-1-01.jpg

    http://johnkvintageguitars.homestead.com/Effects/Fuzz-ODs/Fuzzulator/FUZ-1-02.jpg

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    Replies
    1. Very nice work once again John!

      I think i may need to check that board of mine...
      +m

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    2. Just played with the circuit for a while. The switch is just as i remembered it. There is a distinct difference between modes, but i wouldn't call it huge. Nevertheless, both modes are usable.
      +m

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  4. Just finished mine - a great fuzz sound! Very Eric Johnson and extremely quiet when you're not playing (with single coils!) - big thumbs up. I used 1N60's instead of 1N34's and sounds just perfect. I've built way over a dozen fuzzes and this is my fave yet :)
    As an aside, love Demeter stuff - the trem and compressor are on my pedal board fulltime. Now the fuzz will join them!

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  5. hmm. the switch is pretty drastic on mine.

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  6. Swapped the input cap for a 10n instead of 20n - this reduced the boomy bottom end to more realistic levels as I found it overpowering at stage levels.
    Hope this helps!

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  7. Got mine finished last night. Sounds very much like my AC128 FF, but with more gain available. I used 1N60s as well since that's all I had on hand. There is definitely a fairly big change on the switch. I usually prefer one diode switch option over another on my pedal builds with this option, but on this, I like both modes pretty equally - both settings very useful.

    I think I will try swapping that input cap as Philly suggested or the tone cap. I did use a 25k for tone since i didn't have a 20k so that may have affected the tone control a bit. I'll get the 20k before the next build and socket those two caps to play with the tone a bit.

    Thanks again for the layout Miro - Very happy with this one

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  8. I finally got this one put together with correct pot values. It's a really nice & creamy fuzz, which is what I'm looking for. As mentioned previously, quite with single coils but a little bass-heavy for me. I used Philly's 10n input cap suggestion and still would like a little less bass so I might try a slightly smaller tone cap. My switch doesn't do much either so I might just leave it off. Thanks for putting up the layout!

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  9. Did anyone wrote down any voltages to compare with mine? I do have sime issues. The LED distortion does not work at all and the germanium one does not sound as expected...

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  10. Hi! The switch is it on/on or
    on/off?
    thanks for a great site!!

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    Replies
    1. looking at the wiring (and John Ks photos!) you're only using one side, so its a case of just shorting out two wires so it shouldn't matter which sort of switch you use (I'm using one side of a dpdt!)

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  11. I'm getting close to you John Kallas ;) Here are some pics:
    https://www.flickr.com/photos/95025812@N07/15467512650/
    https://www.flickr.com/photos/95025812@N07/15032318364/in/photostream/
    https://www.flickr.com/photos/95025812@N07/15466938978/in/photostream/
    Lovely fuzzzzzzzzz :*

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    Replies
    1. the links dont work for me. and i was really excited to see.

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    2. https://www.flickr.com/gp/95025812@N07/G7h9HA
      https://www.flickr.com/gp/95025812@N07/04PGM2
      I think will work now :)

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    3. Very nice etching Ej. I use photo paper laser printed on my builds. I like yours better.

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  12. This is a great fuzz. Built with OPA2134 and a 22n in place of the 20. Time to box it.

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