Leaving tube amps on.

I have not owned high-powered tube amps.  None of the amps I’ve owned really required much warm up.  I turn them on and start listening immediately.  If they seem a bit off, that goes away in a minute or so.  If the sound is enjoyable right from the start, even if it is less than optimal, why would you not start listening immediately?  If you sessions are short, it is even more imperative to start immediately.

If high power tube amplifiers are as hazardous as outlined in several post above, then how come they are not banned in the state of California?

Worrying about tube seems a little strange.  You knowingly purchased and expensive amplifier with a large number of tubes.  Do people who buy exotic Italian supercars worry about the cost of an oil change?

Not to derail this topic but I've been thinking of getting a tube preamp. Is there ANY safety concerns leaving them on 24/7 especially the models with tube rectifiers?

Don Sachs had addressed this subject, some time ago. If I remember correctly, he had suggested that it is good to turn the tube gear off, when not listening.

I was first introduced to Valve Equipment in the early/mid' 90's and was quick to move over to the schematics using Valves in place of Transistors and Semi Conductors.

I had my first Valve Amp' Pre and Power commission built, and the EE who at this time had a good few years of working with Valves to produce Audio and Studio Equipment gave me as a newbie a clear warning.

Valve Equipment is not a Turn On and Forget device.

Valves in use need monitoring during use and after Power Off.

I have kept to my side of the Bargain for the best part of 30 Years and see no need to make a change. The same EE remains a friend and has produced further Power Amp commission builds for me. 

Red Plate is common on a Output Valve and is a result of incorrect Bias, where increased Voltage is enabled.

Everything in Valve Talk is about reliability, maintained Bias is extremely important.