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.

Tuesday, October 31, 2017

Landgraff Dynamic Overdrive/Clay Jones Overdrive

Probably two of the most hyped Tube Screamer clones around. The only real difference between the Dynamic Overdrive and a TS808 is the clipping switch, offering symmetrical red LEDs, diode lift, and asymmetrical silicon diodes. The Clay Jones Overdrive is mostly the same, just without the clipping switch (just LEDs), and a Burr Brown OPA2134 in place of the JRC4558 opamp. If you want to build the Clay Jones version, omit the 1N4148 diodes and place a jumper between pads 2 and 3 of the clipping switch pads. Like most Tube Screamer clones, what you use for Q1-2 doesn't matter all that much. The Landgraff uses 2SC1815 transistors (BCE pinout) and the Clay Jones uses BC546B transistors (CBE pinout). Alternatives would be the usual 2N3904, 2N5088, etc. The layout below follows the more common CBE pinout. For a drilling template, use the Cmat Mods Signa.




16 comments:

  1. Still better pcb design, than landgraff has.

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  2. Hmmm, is it just coincidence that the latest Wampler podcast was about this pedal's origin? Hehe.

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  3. Built it and works fine. The led clipping sounds immense but the asymmetrical Si diodes sounds too farty for my taste. Thanks for the layout!

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  4. Sorry I'm new to to this, but what's the purpose of the two red LEDs, D1 and D2? would it make much of a difference to leave one out? thanks!

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    1. Those are the diodes creating soft clipping. You can build it without, but it won't sound right. Other diodes can be used tho, like 1N4148s.

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  5. Replies
    1. Google "Clay Jones Overdrive schematic". First image that pops up is it.

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  6. There is inconsistent layout of 4148 diodes on the pictures. On the general (top left) image, the orientation of the diodes is TOP TOP BOTTOM (strip). However on the both right images (colored wires and PCB design) they are oriented BOTTOM TOP BOTTOM, which makes no sense, since the left two are connected in series and having opposite polarity would make them unusable.

    Or did I miss something?

    Also have nearly finished soldering, will try to put there 47pF instead of 51pF since this is the closest I can get in local shops. Then I will let you know if this works.

    Thank you for all the effort. This site is wonderful.

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  7. Tried to build this, works overall good. But setting gain over about 20% makes it whistle - frequency and volume depends on gain settings. I even obtained audio-suitable power adapter for guitar effects to be sure it is not power input. Any ideas? I will probably need to get oscilloscope.

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  8. What is the correct diode position?

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