Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Hello All,

First off , thanks in advance for any advice you can give me. I purchased a bandit 65 about a week ago at a fair price ($50). As the amp didn't come with a foot switch I had NOT had a  chance to use the clean channel until today.. when I found this problem. When I have the clean channel on 4 or higher I noticed a really bad farty (no other way to describe it) like distortion when I laid into it. Almost like speaker distortion. I immediately hooked up to another 12" - 8ohm speaker to see if that was the issue.. and no.. .still the same. Speaker is good. I then went back to the gain channel.. and it was doing the same thing.. but less obvious as I was using more gain which would cover up the issue. I was under the impression that these amps usually have good volume and some decent clean headroom.

Any advice on where to start would be great. I have done some minor work on tube amps... but solid state is something I have never attempted and could use some guidance. Seeing as the amp is probably almost 30 years old, I changed out the 2 main filter caps (2200uf@50volts.). I did it more then anything as habit. I am so use to switching out the filter caps on old tube amps, I figured for the $2 I spent , it wouldn't hurt (though I do not suspect this is this issue).

Below you should find a couple of links to a schematic and layout in the event this helps anyone in leading me into the right direction.

Again , thanks again in advance for any assistance!

Cheers!

Tim

http://share.shutterfly.com/action/welcome?sid=8AaMXDdi2ZOHMw                     (Schematic)
http://share.shutterfly.com/action/welcome?sid=8AaMXDdi2ZOHRA                      (Layout)

What are you driving it with? Guitar, any pedals, etc.?
If up to "4" it's clean, and above 5 it farts, *maybe* it's receiving more bass than it can handle.
It's an excellent amp but not 7 string metal monster.
Good luck.