This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Friday, March 13, 2015

Dr. Boogie Distortion

100 layouts! Thanks to everyone who visits the blog and a special thanks to those of you who have built and verified some of these layouts.

The Dr. Boogie is a JFET-based amp emulator of the Mesa Boogie Dual Rectifier Solo head, designed by ElectraTabs over on the  DIYStompboxes forum. It creates a unique high-gain distortion effect. 

Most layouts and builds of this effect I've seen are in 1590BB enclosures. This one should fit in a 1590B, but would probably be more comfortable in a 125B. Use right angle PCB mount pots and mount them to the board from the solder-side. Mind the EQ row of pots are oriented 180º differently from the top row of pots.



16 comments:

  1. you can mark this as verified,but my tonestack isnt working at his best, didnt have the 220n so i used some 270n and some resistors i had to substitute, plus the gain pot where i used a 500k as im out of 1m, but i tried with amp pots(too big for the enclosure and with caps from my amp part bin its way better but wont fit in the 125a...)

    so component seem pretty critical here. but nice crunchy, distortion.

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    1. Thanks for verifying! Yeah, I think having the right components really helps nail the sound. It's not like a BMP where just about anything in the ballpark will probably work.

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  2. https://www.youtube.com/watch?v=efl_F6scmCk

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  3. Following Gaussmarkov schematic, the 220pf cap on Q4 (the bottom right one on this layout) should go from S to G of the same Fet, not to Q5 G. Easy fix if you turn the 1uf cap down and put the 220pf ricgt next to it, Congrats on the Layout!

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    Replies
    1. Thanks for catching that. Layout has been updated

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  4. what is the use of the trimpot ? if you say bias, what is a bias used for ?
    do we need to turn it to middle for default ?
    max or min ?

    :) thank you mate.

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    Replies
    1. The trimmers are there to allow adjustment to the amount of voltage going to the JFETs (aka biasing). They're used in a lot of circuits with J201s, especially in amp emulating circuits. Typically you want to adjust them so that the drain pin of the JFET is getting 4.5 volts, then plug it up to an amp and adjust the trimmers further by ear to get the best sound.

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  5. Hello capacitor 1uf not be without polarity ?

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  6. Build this one today!great effect. Great design! I've milled my board with a cnc machine.my first thought was to use a 1590b but no...it's a boggie!!!it needs a big enclosure!! Anyway...fired up right away.it's a bit treblier than i personaly like, but other than that i believe it's a must! I dislike distortion boxes, but this one is a keeper!thanks mate!
    Savvas

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  7. hello good afternoon, and made the circuit, but when I move the pot to gain this makes a bad distortion, and tried calibrating the trim but still the same as the signal is cut, and replaced the J201 but the sound quality is the same, somebody could help me? and when I touch the tip of the knob pot interference is heard, as if making gnd. and I chcado welds and my views are right.

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  8. hello good afternoon, and made the circuit, but when I move the pot to gain this makes a bad distortion, and tried calibrating the trim but still the same as the signal is cut, and replaced the J201 but the sound quality is the same, somebody could help me? and when I touch the tip of the knob pot interference is heard, as if making gnd. and I chcado welds and my views are right.

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  9. The led is indicator on/off? Can I use the led on the 3pdt ?

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    1. Yeah, connect that pad to the anode of the on/off LED, and connect the cathode to the 3PDT. If you like to wire the LED differently, just ignore that pad and omit the 2.2k resistor that connects to it.

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  10. My dr Boogie's bass control does very little, almost nothing. Is this normal?
    Thanks

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  11. Great work! A small detail: mirror the perfboard underside traces. The way they're put, it looks like a top view. Checked the pinout of the j201 and the need for flipping the underside traces makes sense. Anyways, guess whoever faces this project will notice it.

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