#1
the sound that comes out of my amp, which is the vt50 vox, is sounding a little weird.

im not sure if its the tube or the speaker. sometimes its goes loud and then all of a

sudden it goes quiet. anyone can help?
#2
I highly doubt it has anything to do with the tube. Preamp tubes will last awhile and it's not a part of the power amp circuit so even if it was bad it just wouldn't work. There would be no volume problems. You might want to ask GB&C. And if they can't help you, it's time for a new amp.
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#3
Its gonna be the SS section of the amp doing this. The volume surge thing is a common issue w SS amps. In most cases its not economical to fix.
#4
Hey check out www.valvetronix.net. It's a set of forums devoted to your amp.

As ridiculous as this sounds, MOST of the volume spike problems on this amp are a result of dirty input jacks. I don't understand how a dirty input jack can cause that issue but apparently it's true.

Mine was only 4 months old when I had the problem. I purchased some electrical cleaner, sprayed it in the jack and then worked an input cable in and out a few times to work it in. I sprayed it in all the jacks.

The problem immediately went away and never came back.

Check out the site I sent you to, the forum moderator is extremely helpful and he's the one that pointed me in the right direction.
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