Mesa Rectoverb 25 Tone problem

[Crusader]

Hi, my Rectoverb 25 seems to have a problem with the Bass Tone on the clean channel, it doesn't seem to change as I turn it up or down. Can anyone suggest what this might be, and what has caused it?

cheers, Doug

One of these things

Edited June 6, 2022 by Crusader
photo finish

[curtisa]

Fault around the bass tone pot would be the obvious check - open circuit between the bass pot and surrounding components, faulty bass pot itself, caps on the bass circuit have drifted in value or gone open etc

Guitar amp tone circuits are usually pretty easy things to navigate. 90% of the time they're just variants of a design Fender popularised back in the 50s,

[Crusader]

Just for the record there's a couple of reasons why I suspect something wrong with the amp. The sound-tech guy moved it around one time while it was still on and he wasn't very careful with it, and the drummer keeps turning the power off at the wall at the end of gigs. Can't be good for it

Or it might just be the valves getting old