Is it OK to leave a tube preamp on all the time?

Excuse me while I go knock on a piece of wood... OK, that done, I've had wonderful luck leaving my preamp on 'all the time' for nearly a decade. I only power it down for moving or cleaning. Oh, did I mention that I've never had to replace the tubes?!? Way to go Michael Elliott (Counterpoint).

24/7 operation definitely shortens tubes' life in ALL cases.
Moreover your electricity bill grows.

Unswitching tube components after the tubes rich the steady state(10...15min for preamps and other small signal tube components) will NOT shorten the tubes' life.

Switching back tube components after they've riched an initial state(5...7min for preamps and other small signal tube components) will NOT shorten the tubes' life.

Under the initial state we should define the state when no emission of electrons takes place from cathode i.e. the tube is literally cold including the tube base if such exists.

The positive issue living 24/7 tube component operation is that your system is always ready to play. Some components improve the sound during staying unoperated for another hour after the steady state but only on couple of small quantums of relative improvement(Someone recently posted a thread about quantum-tweaking units:^)-).

The power tube amps can be maintained the same way with 1.5x...2x longer intervals(think logically!).

These thoughts shared with me by VTL customer service and they realy work.

IMHO it doesn't make a sence to live components overnight without work.
I often call the babysitter to turn my tube-rig on(just only one button) when I finish working so I can come and listen.

My Moscode Super-It (3 l2AX7s) came with explicit instructions to leave it powered on at all times. To reinforce this, it doesn't even have an on-off switch. Harvey Rosenberg claimed the tubes would last for a minimum of 3 years left on 24/7. I've had it for over l5 years, have never blown a tube, and have replaced them every once in a while out of some feeling that I ought to, but the pulls have always tested good. As they say, YMMV.

Small-signal tubes are usually rated for about a 10,000 hour lifespan, give or take. They will often last a lot longer, but they start to get noisier and sonic quality does start to degrade. So if you leave your preamp on 24/7, 10,000 hours is reached in a little over a year. If you are willing to retube your preamp every year, then no problem. Otherwise, turn it off when not playing, and you'll probably get 10 years or more of tube life. Power amps are even worse, with output tube life of a few thousand hours and much higher replacement costs.

I have a question. Do you guys turn your stuff on and let it sit for the warm up period before passing a signal through it?

It seems to me that waiting an hour for an amp to warm up is a bit extreme.

I guess what I'm really asking is will it harm the Amp/pre-amp to start listening to music while the tubes are still cold/unstable?

Thanks in advance. I'm a little new to the tube game