Flamin' Marshall AVT 20!

Anything to do with the things that make the music we listen to.
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Location: Sheffield


Post by chris661 »

The spring line is mechanical, though, which is why I wondered about microphony.

I'd check to ensure the Reverb pot is fully operational (try some contact cleaner in all the pots to be sure) next.

Can you record the sound its making so we might advise where to look?

Posts: 5
Joined: Tue Jun 12, 2012 12:36 pm

#32 avt 20

Post by johnyk »

It's been a while ..... but finally fixed all the problems with the amp.

The second saturated guitar sound was the main amp chip, something wrong with it, so I replaced it again ebay -

LM1875T National Semiconductor 20W Audio Amp IC LM1875

and works fine the original problem of the components burning out must of been the dry solder then the further burning out of the components was because i didn't put the amp fully back together earthing it properly when i tested it.

There is a slight noise on the reverb that i have read on another thread, because it is too near the rest of the workings power and such like.... I'm going to attempt to move it to the bottom of the amp or replace it with a larger one that i have acquired from an old peavey combo... if its possible.

One other thing i would like to have the internal speaker switched on whilst i plug in a cabinet at the same time, I've got a 1 x 12 cab i'd like to use to make it sound a bit bigger. any advise on this or the putting a larger reverb unit it would be great, thank you all in advance.
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