Help MKIV

[miqueas92]

Hey,

I use a Digitech GSP 1101 with my MKIV as I can switch between the gsp and the MKIV tones.

Yesterday, the MKIV pre amp stopped working but the power amp side is working as all the GSP
tones worked.

I unplugged the GSP and the MKIV still did not work.

Any ideas of what could be up¿¿

Thanks, Mick

 

[zebpedersen]

Is it in the loop? Is it out front? What's the signal path.

 

[miqueas92]

the gsp is in the loop.

But when I unplugged it from the MKIV the MKIV still didn´t work.

Mick

 

[Fronzil]

does the MKIV work when you go guitar > amp, with the FX loop NOT engaged?

 

[stokes]

Try connecting the effects in to the effects out with a straight guitar cord.
If that makes it work you need to either clean or replace the effects loop jacks.

 

[miqueas92]

Amp is at church so, will try your suggestions asap.

Mick

 

[straitouttahell]

It may sound stupid but... Check that the FX loop is not engaged

This makes me silly from time to time

 

[miqueas92]

Well,

It turned out to be a bad V1 pre amp tube, a Mullard :x

Mick