Leave tube amps always on?

On the LTA website it mentions that they drive the tubes with 1/3 of the amount of current that typical tube amps use which is part of the recommendation.
Also many believe that tube life is shortened because of multiple power up / power down cycles. Consider the physics of a cycle- abrupt current and heat to a cold tube and tube glass, thermal expansion differences between materials- e.g. glass and different metals and pins that are expected to hold a mechanical vacuum to survive.  Running at temperature and maximum thermally expanded state for many hours then a rapid cool down / thermal shrink after power down.  This happens every power up / run/ and power down.  Thermally and mechanically stressful to the tube elements and glass.  

Most tubes do seem to fail at startup as opposed to failing gracefully while running- similar to an incandescent light bulb.

I would consider leaving them on with an LTA product and see how it goes.

"Tubes, generally speaking, are NOT like light bulbs, so they do not suffer nearly as much from the thermal shock of being turned on."      Actually; the cathode in a vacuum tube is heated by a refractory metal filament, generally tungsten, very much like a lightbulb’s.      Some cathodes (directly heated) are the filament. https://en.wikipedia.org/wiki/Hot_cathode      Even so; as much as I’ve spent on my NOS valves, persuading me to leave them on, 24/7, would be a difficult task.     Glad my Cary monoblocks have separate B+ switches, so I can give the electrons time to start their hot little dance.

It is an irresponsible idea to needlessly consume power.

@avanti1960


That’s the conundrum. The NOS Mullard Tubes, all 8 of them in my 2 amps ( a quad per) are EF2 from the early 1960s, are almost impossible to find outside of LTA and prices are over $200 per tube if you do.  Even LTA acknowledges that unless they find another warehouse in Eastern Asia with 60 year old unopened boxes they will one day soon need to find a replacement tube for their zotl40 reference amp so I may not want to test Mark’s suggestion.

Today I will be watching football with the volume off,and listening to my main system which has a tube preamp. I won’t be leaving the house,so I will keep it powered up even if I go hang with the Mrs. before kick off.