Do tubes wear out faster at high volume?

[Structo]

Are you talking about power tube life?

I find it hard to believe that a current production power tube could last 40K hours.

And is the end of life a catostrophic failure or when the tube no longer sounds good?

[Merlinb]

Are you talking about power tube life?

I find it hard to believe that a current production power tube could last 40K hours.

And is the end of life a catostrophic failure or when the tube no longer sounds good?

No, pretty much any receiving tube. Like I say, the average life is not the same as the "expected life" you sometimes see on datasheets. Average life is easily 40000 hours and is worked out statistically. That's why you get tube amps made in the 1950s still working with the same tubes in. The "end of life" is either catastrophic failure or when the gm falls below a manufacturers expected limits.

[Structo]

OK, yeah I have a old Hammond organ amp that had the original tubes in it when I got it.
Sylvania silver topped 6V6 that still sound great!

I guess I never thought of tubes in terms of the cathode coating being used up.
Makes sense.
The electrons have to come from somewhere.

[jezzbo]

Again thanks for the info guys.

[krash]

When the "electrons come from somewhere" they are replenished from ground, otherwise current isn't flowing.

The problem isn't that the cathode runs out of electrons to give away. The problem is that the cathode doesn't just pass on electrons, but it gets stripped of other material, which causes eventual failure. The electrons just flow in and out just like with any conductor.