Project overview
Inspired by Carl Martin´s original PlexiTone, this is probably the most Plexi-sounding pedal you will ever hear. Marshall Matters!
No one can deny the impact of the Marshall sound on the music we’ve been listening to throughout the years. It is so powerful that even non-guitarists started to incorporate these amps in their signal chain to add its character to their tone. You can’t really blame them, because the added value is undeniable. So what’s even better than a legendary-sounding amp? The same sound, but captured in a device that fits in the palm of your hand and won’t break your back or buck.
Introduction
The Pleximan is a circuit based on a genial plexi-in-a-box design from Carl Martin, but with few improvements. First off – the size. We managed to squeeze all the goodness into a compact board that you will be able to house in a 1590bb enclosure. Apart from that, we replaced the internal transformer with a charge pump. This allows the pedal to run on 18v from a 9v power source, which provides you with more headroom in your tone. To make things even more interesting, we made it possible for you to make your own version of this legendary unit that will include an extended tone stack. You thought that’s it? No way! Our version has replaced the original’s buffered bypass with a true bypass, so you don’t need to worry about your clean signal being affected by the pedal when you’re not using it. With all that out of the way, let’s have a look at what the pedal has to offer in terms of controls.
This ultimate Marshall unit includes switchable boost, as well as a channel selector for your crunch and hi-gain needs. The Pleximan comes with 5 potentiometers – HI-GAIN, CRUNCH, TONE, LEVEL and BOOST. The HI-GAIN and CRUNCH knobs let you dial in the desired amount of saturation for their correlating channels. The TONE control is just what you’d expect from its name – it lets you shape the tone of your distorted signal to your liking. With the LEVEL pot you are able to set the overall volume of the output of the effect unit. There is also the BOOST control which allows you to control the switchable boost when you need to cut through the mix during the solo you’ve waited the whole night to play.
With all the above said, what are you waiting for? Get that Plexi, man!
Controls
Potentiometers
- Boost
- Crunch
- Level
- Tone
- Hi-gain
- Boostsw Footswitch
- Channel Footswitch
Switches
- Boostsw
- Channel
For further analysis on this circuit take a look at this thread on Free Stomp Boxes Forum.
For any technical questions regarding this build don’t forget to check out our Facebook Group and our forum at Free Stomp Boxes.
yupnitski77 (verified owner) –
Good basic OD with usable tones! With my home-setup (Roland Cube and Gibson LP) I didn’t get this one to shine, so I can’t be all the way sure how it’d benefit from a tube amp and a good cabinet. Basically, I got the pedal working right off the bat, but there was an issue with the leds that was my own fault. I used TL084 instead of LM324 because with LM324 I had a high freq squeal when either Crunch or HiGain pot was past 12 o’clock. I suspected the 1044 of that, but changing it didn’t help at all (and yes, I used the “SCPA” ones).
It’s a working pedal and good layout, nothing to complain. For me this wasn’t anything super special, but perhaps that’d change if I had a decent amp/cabinet for testing.