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Amp Humming and Loss of Volumes!! Help.

12/6/2003 12:01 AM
Amp Humming and Loss of Volumes!! Help.
ok, have a crate blue voodoo 60 combo.  
changed the tubes to sovtek 5881wxt's (same as the original tubes).  
when i play, the first 10 minutes is fine.  
after that, the amp volume drops trememdously! i cant even hear anything until i set the volume to 5 or 6.  
at at that point, it starts humming.  
then i turn it off, leave it alone for a few hrs and go back to it then the same thing happens after about 10min of playing again.  
anyone know what the problem could be?  
in desperate need of help.  
12/11/2003 10:29 PM
Have you tried reading through the "Guitar Amp Debugging Page" instructions?  
Clearly, from the description, you have a thermal problem. When something heats up, it does something bad, and won't operate correctly until it cools back down.  
Fortunately, it stays bad once the amp gets hot. Let the amp get hot, then follow the isolation instructions on the debugging page to find out what and where it's failing. The tube pulling and swapping instructions may isolate the problem to a single stage for further work.  
Take the safety precautions on the Debugging page to heart. If it's not a bad tube and you don't have the necessary skills, let a tech fix it. No amp is worth dying for.  
12/12/2003 6:51 PM
Jack Collins

What happens if you put the old tubes back in?  
Do you get the same symptoms?

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