stupid tube question of the day

i run my tube amps 4 hours max. if i want to keep going, i turn them off for 30 minutes then back on.

G_m_c

Why is that?

Tubes are slowly wearing themselves out as soon as their powered up. The circuit design has a big influence on tube longevity and NOS tubes aren't getting any cheaper. No sense in taking a chance on leaving tube gear powered up other than an hour prior to a listening session & then should be turned off when your done.

When powered up, I would think that when tubes are driven by an audio signal as opposed to no signal at all would in fact reduce their life span, especially in tube amps. I have had very old tube gear that still works with their original tubes. Maybe low usage could of contributed to this or again it goes back to how the tube circuit is designed or maybe both.

Samhar, i have very nice (and expensive) nos Mullards and want to maximize their life. I was told by the canadian dealer whose name escapes me to do just that. he seemed to know what he was talking about and i am happy not to take any risks with this lovely stuff. :)

Thanks all. Yeah for sure, no point in leaving tube gear powered on when you are not using it, esp. will NOS expensive tubes. But my issue is that I often turn on my tubed CD player, and listen for a couple of hours and know that I'm going to be listening again in 3 or 4 hours, and the question is, should I turn it off, or not?

Of course to be safe, I could just turn it off. But I'm curious if there is really just minimal wear on the tubes when the CD player is on but not playing.