Sunday, 12 July 2020

DOD 210 FET Preamp

Surprised this one hasn't been done. A nice small and quick build, and should have lots of boost on tap and fatten up your tone nicely. Could be a good platform to mod to taste. Seems to be on the rare side to boot. Only video I could find was a DIY build that has some mods, but you get the idea.




19 comments:

  1. Vol2 to output?

    Congrats on the doctoring too - been at it since '98 myself :)
    Have you created any original pedals, out of interest?
    And thanks for all the effort you've put into the layouts!
    Adam

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    1. Seems there are several docs around, making pedals! Finished residency in '95. Maybe 3 more years of doctoring, then hanging it up. I'll have more time to build pedals! And amps...and guitars...roast coffee, and just do *stuff*!

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    2. Yes Volume 2 to output, I’ll fix the layout. And yes, I’ve got a few original pedals I’ve done.

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    3. Ive started an amp build, hacked together a few guitars at home, but yet to roast my own coffee - gotta try that sometime!

      Zach - any chance of layouts for your own designs? Would be very interested to try building one.

      Cheers

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  2. Verified!

    Built it with J112, 2n5457, 2n5458, 2sk30 (watch pins), and 2sk117 (watch the pins again). The k117 ismy favorite.

    The 2n5458 provides a nice overdriven sound when your guitar volume is half to all the way up, though depending on how hot the pickup is, it can get a little farty. If you want a nice boosted sound, the 2sk117 provides a dirt boost that's pretty nice. Also the tone boost is excellent!

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    1. Hi I would try with BF245 and BF256 the only "real Fairchild" I can get in TO92 and also because i've ran out of my batch of MMBFJ201 in SOT23. What do you think about? I'm a bass player and found these FET sounds not to bad in bass related circuits!

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    2. Can it be overdriven by itself?

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  3. I've used this is a small boost in a few pedals so far. Super easy. I leave out the pot and volume 1, instead using volume 3 as an output into another board. Had J113s so I stuck with that.

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  4. Thanks for a great site! A quick question: If building this as an optional final gain stage for a treble boost/overdrive hybrid, can I leave out the 3.9M resistor?

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  5. I'm completely new to guitar pedal building, and I was wondering if you could help answer a few questions!

    First, what's the dsg? Is there a more formal name for this when I buy parts?

    Also, if I were to add an LED and a footswitch, where would I add this?

    I'm completely new to circuitry, and would greatly appreciate the advice!

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    1. D, S and G refer to the Pins of the FET Q1, which are Drain, Source and Gate respectively.

      For LED and Footswitch layouts, check the 'Offboard' section of this website.

      Good Luck!

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  7. verified with J202. Crisp boost that gets dirty. And LOUD! Thanks for all the great layouts!

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  8. Nice simple build. I am only puzzled with bottom brake strip on 5th row. Why is this brake strip necessary if you do not have anything connected on another side of the same strip.

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  9. Nice simple build. I am only confused with a bottom strip brake (2nd strip from bottom). Why is this necessary when there is nothing on other side of the strip?

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    1. I guess you're right, that cut is pointless.
      I'd say to use the free holes between the two last two stripes (9v and ground) to insert at least a 47uF cap to filter power supply noise, and in case, a polarity protection diode.

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    2. While it's not my layout and the cut is pointless in terms of isolating the track so it can be used for something else, I've done this a lot in my layouts to minimise the size of the 9V track. The supply will be the biggest source of noise in the pedal and so keeping it to a minimum, and especially if it means you can prevent it running next to a track near the output for instance, has the potential to be helpful.

      The 47u is a good shout though, although personally I'd put it below the 220K where there is lots of room to either side

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    3. It's been a while I design my layout, too, and to make some tracks shorter or isolated is one of the thing I tried to do sometime, but more than else with signal track. I try to don't make certain track pass too close (typical example: input and output). I still didn't know that the lenght of the 9v track can make noise, I'm not sure I noticed that beafore or I never got any problem with it.
      Thanks!

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