At band practice on tuesday, I noticed the amp was making a white noise/static sound when I hit a low note/chord. Anything between low E up to B seems to do it, but it doesn't do it when no note is played. Valve swaps haven't helped. I guessed that meant there was a dodgy connection inside that was affected by certain vibration frequencies, and that it was time to go to a tech and open up my wallet again.
One of the speakers also has quite an annoying cone cry so I was gonna try inverting it to see if it helped, which meant inverting both speakers (because the leads between them aren't long enough for a diagonal connection) which meant pulling the chassis to get to the bolt behind the mains transformer.
With the chassis out, I noticed the black lead off the reverb transformer was loose inside. Great, that's probably what's making that horrible static noise. It only goes to ground and it had been grounded through the footswitch jack before coming loose. Feeling gung-ho and hoping to avoid a tech trip, I resoldered the connection, tested continuity and put it back together.
Well that ain't fixed it (and the cone cry is just as bad as before). Am I missing something obvious or is someone going to have to go through looking for a dry joint inside?
Comments
"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
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
it definitely sounds electrical (if that makes any kind of sense) and seems to be coming from both speakers (whereas the cone cry is obviously the one speaker, although both problems have arisen simultaneously )
Does it on both channels, with or without reverb, once the volume is up around 6
will try this out.
Thanks for the suggestions everyone, will report back
Yeah it's still there.
Looks like it's tech time
I will get around to confirming it definitively but does anyone have any recommendations for how to get a 10" CTS alnico reconed?
Bygone Tones - thanks for posting, great reference.
Ddig
So it's NOT the amp's speakers, it's something else.
Apparently he diagnosed it by having a signal going through the the amp while pressing solder joints in turn with a chopstick!