What is this power tube issue?

[Mr. Willy]

Update - it was that glowing blue tube that was bad. When I say glowing blue, I’ve seen power tubes glow blue before, but this was like Cheech and Chong puffing on a Smurf joint blue. Really, really blue.
Anyway, I pulled the two outside tubes first (bad tube was farthest right when facing the amp), and the problem went away. I put a quad of JJ 6L6 (ones that can handle the plate voltage) in and the problem was still gone. It’s a bad power tube. Will order a quad of new wafer bottoms soon. Really happy this is the problem and not something else. Thanks for all the responses!

 

[Donnie B.]

but this was like Cheech and Chong puffing on a Smurf joint blue

If asked to describe a blue blue - and given 1 billion tries,
I'd never stumble across combining C&C and the Smurfs.



Cool you got it sorted out.

 

[Samhain]

Bad tube is a bad tube blue glow or not.

 

[Mr. Willy]

Bad tube is a bad tube blue glow or not.

Sure thing, but none of the other tubes were glowing like that, so…

 

[Samhain]

Sure thing, but none of the other tubes were glowing like that, so…

Most all of mine blue glow for about 45 years Bro.
Its not what cause your issue.
I posted you the definition of that in this thread last week.
Don't know why you choose to believe otherwise.
But whatever.
The blue glow is boiling electrons hitting the glass and a sign of a healthy tube.

 

[Mr. Willy]

Most all of mine blue glow for about 45 years Bro.
Its not what cause your issue.
I posted you the definition of that in this thread last week.
Don't know why you choose to believe otherwise.
But whatever.
The blue glow is boiling electrons hitting the glass and a sign of a healthy tube.

Yes, I know that power tubes can glow blue. I said that already. I was never disagreeing with you. Not sure why you’re being so bullheaded that you missed that, but whatever.