Metropoulos Forum

I have this idea that I'm hoping might work, and I'd like to hear your comments before I buy stuff to try it out.

So, the goal is to be able to switch between clean/dirty in a NMV Marshall based amp that has a tube buffered series FX loop. And to use amp's overdrive sound rather than an overdrive pedal.

I got the idea from connecting the guitar directly into FX loop return and thus bypassing the whole preamp. And I found it's actually a nice clean sound, only slightly muddy, but I hope an EQ pedal can fix that.

The idea is to use dual signal paths, dirty via amp's preamp and clean via eq pedal, and AB box to select.

Let me describe the flow:

Guitar into Boss TU-3 (it has 2 outputs and serves as a splitter).

One output goes to amp input, other goes to EQ pedal.

Then I join both paths in an AB box. So one input from amp's FX send and other from EQ pedal.

I set the amp volume to 10 and it produces the overdriven tone, while the EQ pedal produces clean.

I then adjust the volume of EQ pedal to be slightly bellow the volume of amp's preamp.

So what do you guys think, I don't have an EQ pedal nor an AB box yet, so can't really try, but to me it sounds like it would work.

The only question is if I can adjust the EQ pedal to remove the muddiness that I get from plugging guitar directly into FX loop return. And if the EQ pedal volume increase will be sufficient to match that of Amp's preamp.

Any comments ?

Any luck with this?

I belave it won't work with a SERIAL loop, but might work with a PARALEL one... very simple, the signal from preamp won't hit the poweramp unless it goes to the loop (series).
I think you can1t do it with a regular AB box bc of the series loop, but you can ask for a custom switch that can do the job, changing the signal path from the amp input/loop return and loop snd/amp input at the same time.... thought that myself years ago but never tried though.... good luck