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Hi there, welcome to my blog - La Revolution Deux. It's an odd name - but I like it! Here you will find all the info on my various DIY Guitar effects builds, amplifiers and guitars. Everything from a humble Ibanez tubescreamer to the holiest KLON Overdrive.

You may also find a few effects builds that I am looking to move on - usually in exchange for other effects/gear/cash. You can always check my ebay account to see what I've got up for grabs.

Have fun, enjoy the blog - Fred Briggs :-)


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Tuesday, 20 May 2008

Hermida - Zendrive Project at FSB.org

[NOTE - This post also contains info on the Fuchs Plush Drive & Jetter Gain Stage Red]

Here is the sought after "Zendrive" overdrive pedal. If you're unsure of what these are check out the Hermida Audio Website; http://www.vendio.com/stores/HermidaAudio/item/effects-pedals/zendrive/lid=2384441

And here is a demo video (there are plenty of sound samples on the Hermida website though...);

A full project, presented by the freestompboxes forum member "

Now the Fuchs Plush Drive - Well, it's just a Zendrive clone. Here's the evidence:

And the Jetter Gain Stage Red:

Soulsonic traced one out, here's what he found:

And the Schematic of the Gain Stage Red:

And here's what he had to say about it:

"Yes, it's almost an exact clone of the Hermida Zendrive. The differences are minimal if you can even call them differences. Instead of the "Voice" control, the Jetter has the "Hard/Soft" switch which toggles between two static values of the exact same "Voice" circuit. The 100pF cap has been omitted from the feedback loop of the overdrive section. The Tone control is 100K linear, instead of 50K. A reverse polarity protection diode has been added... that's about it. The opamp type is unknown - the numbers have been sanded off it. The MOSFETs have been sanded as well, but my Atlas DCA correctly identified them as N-Channel Enhancement Mode MOSFETs, which means they are likely the usual 2N7000/BS170 type. Two of the diodes are those same kind of little blue glass ones as Kerry described were in the Zendrive, and the other diode is a 1N60 or similar germanium (also like described as being in the Zendrive)."

Here's the Zendrive topic on freestompboxes for reference: http://www.freestompboxes.org/viewtopic.php?f=7&t=268

Here's the Fuchs Plush Drive forum topic on freestompboxes.org for reference: http://www.freestompboxes.org/viewtopic.php?f=7&t=2411


  1. Hi! I want to built this pedal, is this schematic right.There's some details unmarked on layout.

  2. The layout and schem do not match. Please update component labels.

  3. Can anyone tell me how to make a mosferatu? I'm gonna build this zendrive off of the schematic so hopefully everything will work out.

  4. I have built this on breadboard from the schematics and it works great. Question: I have used Bat43 insted of 41 that I could not find, would that make a massive difference in the quality of the distortion/amount of gain? Great blog BTW

  5. Someone posted pics of the guts of a Zen and the diodes were (2) BAT 46 and (1) germanium

  6. I built this pedal on pad-per-hole board and it works great. I used the schematic exactly except for the wiring of the pots. I used the layout picture for that. The schematic and layout are quite different from what I can tell. It sounds great though!

  7. i built a couple more of these on pcb's. They sound awesome!

  8. I can confirm that there are 2 bat46's and 1 1n34a in the clipping section as well as the fet's. Just de-gooped mine today.

    1. sorry about this probably stupid question: how do you de-goop your circuit?

  9. I just finished this project on pad per hole. It is true that the schem does not match the layout. I did use the layout anyway I just found the right componants from the schem and substituted them in. I also made it as a three knob pedal with the voice control as an internal trimpot.I had already drilled the inclosure for a fuzz project that I decided to hold off on. So I recycled it. Besides I don't think I will change the settings that much. I did not have any schottky diodes (bat46), so I used 1- 1n34a and 2- 1n270. For the mosfets I used 1- 2n7000 and 1-bs170. Everything else is the same. Really I am not sure how much the 1 mosfet and 2 diodes really changed but it still sounds great. I was thinking of selling it while I was making it but now I don't know.

  10. hi can i order 2-3 PCBs from someone here that know the job?

    (authorized paypal).

    please send me an offer to :


    also, where can i find the right component value ?
    thank you ,



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