Western Electric 300B problem

pops and tings can happen the first time a tube heats up. Loss of vaccuum is the correct diagnosis. Sounds like a bathtub curve infant failure. Most tubes don’t make an unusual smell when heated up but I’ve never heated up a new Westinghouse.  If something is going to burn off a substance used in the manufacture, it will do it the first time it is used.  I’d mention this when I contact the warranty representative.

Now you get to see how good and convenient the warranty is. Please report back.

Jerry

I had a heater die (go open) lately on an 80 year old tube.

Have you compared EMLs?  I use those in my dac.  where do you buy your ACMEs?

@sns  Interesting that upscale burns in expensive new tubes.  There are those that say tubes "should not be shipped after they have been used as the heat makes the filaments more brittle".  I think if you can ship them before making the filaments glow, it is a good idea.  that said, I buy a lot of used tubes and generally, almost always, don't have a problem.