The Benson Preamp is pretty popular, but 2M pots are hard to find. This is a modded vero layout using a 1M bass pot. To make this change and keep the same frequency response, resistances are halved, capacitance is doubled. Note that the Drive pot value also had to be halved.
I’ll add a regular size layout with normal 1/4 resistor later – just felt like a larger layout for this one.
BENSON PREAMP – MOJO VERO LAYOUT
BENSON PREAMP – MODDED SCHEMATIC
As you can see, the response is nearly identical between the stock and modded values. This will change a little using stock cap and resistor values, but it will still be pretty close.
