welcome to Apocalypse Audio, your haven for DIY guitar effects in the end times. so, start prayin to the fuzz gods, savin up those parts, and remember, when the big one goes off- keep your transistors shielded from those pesky electromagnetic pulses!

29.11.09

WAMPLER - CRANKED AC

recently while browsing a certain clone kit site, i stumbled across the schematic for brian wampler's cranked ac design. having been on a serious ac kick a while back, i was never able to find the schematic, so this was kind of a cool find. the cranked ac at first looks like your run of the mill jfet type distortion box until you notice that wierd parallel fet configuration. ecaxtly what this is supposed to do to the sound i don't know, but it is a rather interesting little tweak. i'm sure that this could be adapted to just about any transistor type, and wonder if it has any of the same kind of properties as stacking ic's.

i redrew the schematic and made up an eagle verified pcb layout which should work ok. if anyone gets it built please let me know .  you can keep up with all of the latest on this subject HERE.


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LAYOUT IS VERIFIED!




9 comments:

  1. Jeremy23.2.10

    If I wanted to use the above layout to send to a custom PCB maker such as the people at SparkFun.com, how would I go about doing so? Is there a way to import that graphic into Eagle CAD? Or do I just need to recreate the schematic myself and make a board layout?

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  2. i would try someone like Madbean effects. he can print up a one off for you no problem

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  3. Has anyone used this PCB layout?

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  4. I didn't follow the layout but I did made one based on this schematic. I also found different schematic for cranked ac but not so different. just a one cab and a register with different values. anyway I built one but it just sound wrong. I'm not sure it was my fault but I did dubble checked the schematic and my layout couldn't found any mistake. so I think it was what it supposed to sound. anyway it works perfect but just doesn't sound so great. all the knobs work fine. hate the sound

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  5. This comment has been removed by the author.

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  6. JFETS have to be biased to around 4.5-5v on the drain in order to sound their best. all JFETS are a bit different, so adjust the resistors on from drain to 9v on each one, and your pedal will sound much better. many use trimpots for this job, but Wampler prefers not to. I wanted to keep the design true to his, so I left out the trimmers.

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  7. Your layouts are awesome. I love the third one. These parallels and dots may be complicated at first. But once you get to know them, navigating around would be a lot easier.

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  8. Wow, its sounds amazing. I found a 10w amp in a skip which I thought would be great for the kids or just to test circuits late at night. It sounds awful... usually.

    I plugged this into it and it sounds awesome. Thanks for the nice clean documentation and layout.

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