Problem with my 5150 squealing

[JerryP]

I'm way behind here, but I thought I've answered them all. I've been having some issues with my email account doing weird shit on me lately too.
Jerry

 

[kirk]

I tried putting the preamp cover on and it didn't help. Then I tried swapping relatively new tubes all around the preamp and that didn't help either. What are the chances that the problem is in the power tubes?

could be power tubes as well ,but what probably happened is ,the tube sockets are soldered to a pc board in that amp and are extremely subceptable to heat causeing solder joints to go bad and with you pushing and pulling new tubes in and out alot,has probably broken a joint lose causeing your headaches

Never seen an issue with a tube socket solder joint on a 5150 in all of them I've ever worked on. The power tubes are mounted above the sockets and since heat rises that's not ever going to be a problem on this amp. The preamp tubes are mounted sideways and they don't get hot enough so it's not an issue there either. A bad solder joint on a tube socket isn't going cause feedback.

If there were no issues before you started messing with tubes I suspect it's a tube issue. The 5150 will weed out bad tubes real fast with all the gain it has. The preamp tube cover must be installed as the foam acts as a damper to help prevent microphonics.
Jerry

agreed jerry but i have had two of them in here where the guys were pulling tubes in and out ,running the amp for hours trying the different tubes and both of them had bad joints on the legs,maybe not the squeal issue and i agree the 5150's crazy gain will weed'm as you say,and the cover on this amp makes a huge difference on the noise ,but i never say never,cause a soon as i do it happens

 

[kirk]

To psychodave's remark above...

I ain't IGNANT!!!!

What kinda backhand is that?!?! I was simply saying, considering there are masses of professional musicians out there who couldn't give a rats' ass about tube covers, cables or the like because they're too damn busy touring the globe and playing guitar, the fact that a bunch of monitor tanned freaks like us discussing the immense minutaie around such matters is baffling. We must have a lot of time on our hands!!

Bastid!!
V.

i like this statement