So, a couple of years back my vc15 suddenly packed up - had it serviced and it turned out the main transformer was faulty so it was replaced and the amp worked fine, except for a popping sound when i switch it off which i've lived with.
Plugged it in today and there was a lot of noise very similar to what you hear when trying to tune a radio station in - lots of static/white noise although you could hear the guitar in this noise but distorted on clean.
The led is no longer working on the "drive" button and the only knob (other than the master vol) which seems to control any sound is the reverb knob, so turn the reverb knob right down and it cuts the noise almost as if its acting as a volume knob now!
I've checked each one of the valves, swapping them out one by one for my known working spare valves (it was revalved when the transformer was changed too) but thats made no difference whatsoever!
Any ideas guys?
Comments
It sounds like it might be a low-voltage power supply problem or a faulty IC (+15V operates the switching, +/- 15V supplies the ICs for the FX loop and reverb). I think a failure in the +15V rail would probably give you something like you're getting.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Just because I don't care, doesn't mean I don't understand." - Homer Simpson
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Just because I don't care, doesn't mean I don't understand." - Homer Simpson
You may be able to see a heat discolouration on one of the two drop resistors, but that would only confirm which of the two rails is affected.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Just because I don't care, doesn't mean I don't understand." - Homer Simpson
Turned it on again and its still doing the same - not sure if its because i disturbed any dust in there but it did have a smell as if it was overheating electrically too.
Off to a tech i guess.