How can do you extend the life of your tubes?


My amp premp and cdp are tubes. I read years ago, proportionatley, the most tube wears comes from powering up. And shutting down, and then powering up shortly is life shortener for sure. Shortly is too vauge. What do you tubers do to lenghten the life of your tubes, especially when we're talkng NOS and the like? thanks in advance.
128x128warrenh
My pre and power amps all have standby switches that provide a much reduced current to the tube filament, thus avoiding thermo shock when powering up from cold.
I keep mine turned off when not it use - only warm up 30 minutes to an hour before listening.
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I only turn my tube equipment on when I going to be listening. A standby switch is nice if you have one (I do on one of my amps) but I would still turn it completely off if I wasn't going to listen a for a long time like for a day or two.

I would not turn an amp back on (like if you were changing cables or ?) for at least 5 minutes and probably give it a half hour and I wouldn't do it that often.

Another factor in how long tubes last is how hard the designer has chosen to run them.

When you get a new set of tubes I am a firm believer in NOT running them 24/7 or close to that just to speed up the breakin. I think best, for sound and longevity, is to run them 3-4 hrs then let them cool completely (4-6) then start up again. Do that for just the first week or so.