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Forum Home > Layout Gallery - GuitarPCB Build Documents, Mods and Tips > Plexi Plus

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What makes the Plexi-Plus so exciting compared to other circuits?

  • It uses individual JFET gain stages to create the ultimate variety in a distortion pedal. No op-amps or clipping diodes are being used.
  • It was common for Plexi Owners to use a patch cable to connect 2 of the inputs together.
  • This is what Plexi-Plus does by using two stages in parallel, one for the bright channel, and one that ties in the fat tone of a full stack. Together you can come up with your own unique tones.
  • Easily dial in Hendrix, Zeppelin, AC/DC & more. Even plug in a bass and it's Bass Ready.

The circuit was originally based on a popular circuit by Marvel™, however we have taken it much further by enhancing the Treble channel and a few other tweaks thanks to some serious innovation by our resident circuit guru Chris as well as a lot of testing (scope and ears) over many months by myself and Wilkie1.

There was much about the original we liked but took liberties in removing fizziness & hiss associated with the original circuit when cranked. Now it's a 100% completely natural sounding on any level. "PLEXI IN A BOX"

*GuitarPCB is in not affiliated with Marvel™, and should not be misrepresented as a clone. All Copyrights, Trademarks, and Artworks remain the Property of their Owners.

Plexi-Plus Build Document

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This circuit also works great with our active Tone TwEQ circuit adding additional gain and tone tweeking options for the modders out there! Also try the After Blaster for an extra stage of Hot-Rodded Plexi madness that can be activated or bypassed.

Highly recommended for the Plexi-Plus:

After Blaster for High Gain Hot Rod Fun

50k Bias Trimmer

Another interesting Mod is to add the Tone TwEQ 3 Band Active EQ to your build:

Here are some Tone TwEQ'd builds by Trom:

Recommended accessories:

1. Barry's Famous Pot Condoms™ .

2. 3PDT Wiring Boards .

3. Barry's Best Pedal Hookup Wire.

4. DPDT Wiring Boards - Perfect for Mods

5. DC Power Jacks 2.1mm

6. Common Anode LED (Optional to Standard LED)

7. Plastic Bezels for Common Anode LEDs

8. Pot Condoms for mounting in tight quarters over potentiometers

9. GPCB Secure Mounts - For mounting with room to spare

February 27, 2018 at 12:35 AM Flag Quote & Reply

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