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.
warrenh
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.
Well tube amps should never be left on unattended. Too many fires for a tube amp to just sit runnning all day long with no one watching it.
Tube preamps on the other hand can be left on 24/7 (usually)
I leave my four tube VAC Standard preamp on 24/7
As i am listening to music all day every day..
If all I listened to was on weekends.. I would turn it off betwwen listening sessions.