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.

Thursday, February 12, 2015

Earthquaker Devices Speaker Cranker

Here's a simple one that should fit nicely in a 1590a. EQD's take on the Electra Distortion circuit. Instead of having a pot coming off the end of the circuit, the volume is controlled by a pot coming off the emitter of the 2N3904. It's really more of a gain control than volume and if you wanted to, you could add a master volume control coming off the output. Who doesn't love more knobs, right?


14 comments:

  1. Great layout, pedal and blog! :)

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  2. The best Electra's based boost!

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  3. It seems that the pot is b10k
    http://i.imgur.com/8O6zn56.jpg

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  4. Have you ever considered adding the schematics as well or do you just do the layouts based on tracing out the existing pedal circuit board? By the way, amazing site, I can't imagine the amount of time you have spent on this.

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    1. Thanks, man! Most of the schematics can be found either by googling for them or looking on Freestompboxes.org. Guys over there trace a lot of stuff.

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  5. hi.
    just bread boarded and i have replaced 0.47 cap for 68 and it sounds nice.
    really nice pedal.

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  6. Hey,
    just build the circuit and I get a drop of output volume. Only cranked at maximum it's about unity. Should I try other diodes (I used 1N34A) or change the operating point of the transistor? Any suggestions?

    Regards

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  7. I've built a couple and they've all been plenty loud. Well above unity. You can try other diodes, but also make sure you're got the right resistor value going from voltage to the collector. Might not be biasing correctly.

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    1. Yeah, changed the diodes to 1n4148 and now it's right above unity as well. Different sound, but still nice! Thanks for the reply.

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  8. Hi there, I really want to build this one... how I must wire a Master Volume Pot (V) to this circuit? PCB's Output to V1 & V3 (jumpered) and V2 to 3DPT (output)...? Thanks in advance!!

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  9. Sorry... V1 to ground, pcb output to V2 and V3 to 3DPT output, right? That makes sense? Thank youuu

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  10. V1 to Ground
    V2 to 3DPT switch
    PCB out to V3
    should work better

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