A Guitar And Gear Support Forum

I built a clone of a Ramble Fx 'Marvel Drive', using a purchased printed circuit board. The original pedal is aimed at making a non-Marshall amp sound like a Plexi Super Lead, with a switch that emulates the differences between the 50w and 100w models (changes the power from 9V to 18v).

When it was completed, there was something keeping me from bonding with it, which was the overt brightness, and the 'feel under the fingers.' The latter is the case where a Plexi is a tighter version of a Fender Tweed Bassman. So, it has to have a balance of woolly harmonics, tight punch and a little growl.

Having recently acquired a real 1972 Marshall Super Lead, I decided to do A-B comparisons of the pedal vs. the amp, to tweak the pedal to sound like the amp. The pedal went into the '1965 Twin' channel of my AMI Mixmaster and both amps went into a 4x12" Marshall cab.

Mission success by cutting the bright cap across the Bright Channel volume and then trimming the Field Effect Transistor (J-201) bias to values other than the instructed values.

It now has the correct feel, timbre and will sound authentic in a dark or bright amp.

What I used in this project:

Awww, c'mon, you can't just throw in that pic of the green guitar with the p90 in the middle position and not tell us anything about it. It has the look of an instrument that's a mad scientist might use. Is that one you use for testing?

toomanycats wrote: ↑Sun Apr 20, 2025 1:05 pm Awww, c'mon, you can't just throw in that pic of the green guitar with the p90 in the middle position and not tell us anything about it. It has the look of an instrument that's a mad scientist might use. Is that one you use for testing?

Spot on. It is a guitar I built in the 80's to be like a Steinberger, then in the 90's added the wings using some leftover Honduran mahogany. Schaller bridge and tuners, maple Mighty Might neck with abalone dots. AMI 'Special' bridge pickup, a 70's Gibson P-90 and a Duncan Pearly Gates neck pickup. One P-P volume which splits the humbuckers, a dark switch a five way (bridge - bridge split+middle - middle - middle+neck split - neck), and a toggle which brings the neck and bridge pickups on in any position.

Accordingly, it can cop a LP / SG, Tele, Strat and a P-90 sound. And, I don't have to worry about abusing it when I am troubleshooting amps and pedals.

That guitar is killer! Congrats on creating that pedal as well!