Rustling noise help

[bluesguitar]

Have a '67 Super Reverb. Plugged it in for the first time in about 5 months. There is a constant rustling noise, kind of a static/rustling that is happening regardless of having a cord plugged in. The volume knob has no effect. It's just constant with the amp on. Any suggestions on where to look first?

[cbass]

First I would clean the sockets then try swapping preamp tubes if that dont work then I would be looking at plate resistors

[mhartman]

Have the electrolytic caps been replaced? My early super reverb did this before I changed out the power caps.

[bluesguitar]

Have the electrolytic caps been replaced? My early super reverb did this before I changed out the power caps.

Yes, I changed all electrolytic caps less than two years ago.

[bluesguitar]

First I would clean the sockets then try swapping preamp tubes if that dont work then I would be looking at plate resistors

I cleaned all sockets with deoxit. No improvement. Will swap preamp tubes tomorrow, and see if that does the trick. I changed all plate resistors to get everything in spec just before I stopped playing it this summer. It was fine then. Maybe a bad solder joint. I hope not.

[jelle]

Was it store in a humid place?

[Reeltarded]

One time I had this problem and it was a pain running it down.. until I noticed my cattle were missing.

-wapppssshhhh!-

[matt h]

(deleted)

[Guus]

Hi Bluesguitar,

my guess, the problem is probably to be found in a cold/bad solderjoint.
As you mentioned you've replaced some electrolytic caps. Well, I would start resoldering that components.
Succes.

grtz
Guss

[Structo]

I've experienced that type of noise with a bad preamp tube before.

[Milkmansound]

unfortunately thats the "something is wrong" sound that can be one of many simple things:

I have seen a bad 12AT7 reverb driver do it
a noisy preamp tube
bad solder joint somewhere
preamp tube plate load resistor
preamp tube cathode resistor
fractured lead on a capacitor
conductive circuit board
lead dress
etc...

[bluesguitar]

Bizarre/not so bizarre suggestions--

if you've tried reseating all the power tubes, ALSO do this with all plugs/sockets. I've had issues where reverb cables needed a little twist/reseat action.

If that doesn't help, er, looks like the humditty done did gotcher carbon comp plate resistors and/or you've got some bizarre RF interference.

Update: I've swapped each preamp tube one at a time to try to isolate a bad one. No change. I pulled the reverb and tremolo plugs, deoxed them and reseated. No change. Going to have to troubleshoot the chassis. Pain in the ___! I appreciate all of the suggestions, but too much humidity just doesn't make sense to me. Why? Ever heard of Nashville? Think they have much humidity? Think they've ever stored a fender amp in a warehouse or studio with no air conditioning for a year or two between use. Just sayin.

[jelle]

Fairly well documented phenomenon.

http://www.guitarplayer.com/article/sho ... games/7179

Google will show many more hits if you were to search for: fender conductive board.

Good luck!

jelle

[bluesguitar]

Fairly well documented phenomenon.

http://www.guitarplayer.com/article/sho ... games/7179

Google will show many more hits if you were to search for: fender conductive board.

Good luck!

jelle

Thanks for the link. I've browsed a few articles, but I don't think this is the problem. The articles mention symptoms of poor tone and scratchy pots. The tone of my amp is fine, and I don't have scratchy pots. In fact, nothing I do affects the constant (low volume) rustling/static. Its just there as soon as I take my amp off standby. I can play above it with some volume, but it's loud enough that it is more than just normal hum.

[jelle]

I don't think this is the problem.

The only way to know is to measure it.

Good luck!

jelle