I’m trying out a new circuit in my test chassis. It’s based on the Park LE 1231 and 1273. Park amps were made by Marshall and some shared Marshall circuits and some didn’t. This one didn’t. It has 3 gain stages and a cathodyne PI.
Here are the original schematics.
The preamp is pretty close, the PI and output section are a little different as is the power rail. One straight out mod I did was adding a mid boost switch that puts a .001 cap parallel to the treble cap in the tone stack. I think this sounds better for overdriven tones.
I think it sounds pretty good. I’m considering build one with EL84s like the original. With the 250p bright cap on the volume pot its pretty bright at low volume but it’s not as bright as you turn it up.
I did a couple video clips.
This is a Les Paul, the mid boost engaged and going through my 1×12 with a Vintage 30. I’m going for a straight rock sound in this one.
This is one with a strat and then Les Paul going into my 2×12 with a Celestion 70th Anniversary and WGS Retro 30.