Turn off or leave on?

My SS amp rebuilder said leave it on.  Been on 4 yrs now. Tubes, turn it off.  except Carver tube amps. Bob told me his tubes are good for 50 yrs.

Mad to leave tube amps on 24/7.  However hard your amp is on tubes and whatever their expected life, if you listen 3 hours a day every day you are wasting 87.5% of their lives.  That will be expensive.

I don't believe Bob Carver that any tube retains its initial quality for 50 years nor that any amp will allow it to.

Some people with Class D amps switched them years ago and are still waiting for good sound.

DACs/SS Pre/non Class A power amps/Streamers/Phono Stages can take many many hours to 'warm up', or rather, sound their best. My previous Jeff Rowland pre was said, by Jeff, to take several DAYS after switch on to sound its best. So, leave those pieces of equipment on 24/7 unless going on holiday etc. If one turnes such equipment off at night, and on when one wants to listen, even an hour before, you are almost guaranteed to NEVER hear your equipment performing at its best.

Tubed stuff warms up faster, obviously, but can still take hours to sound its best - it's not only the tubes, but also the transformers, which can take several hours to reach the optimum operating temperature. Previous QuickSilver Monos/ARC tubed power amps and EAR valve amps took c3 hours before they were up to operating temps.

This seems like a predominately 'tube user site', but I say that 'tube sound' and their limited lifespan, and the degradation of SQ during their life (power tubes), which is difficult to hear/quantify, and the fact that one tube will/may sound different to another, are some of the reasons I left tube use many years ago, not to mention that one never knows if they are really perfoming as good as they can, which, after initial burn in, will be a downhill slope - I almost resisted mentioning their inherrant distortion too! (waits for the bricks!)

I turn everything off before I go to bed and turn everything on in the morning. I pass  my equipment on the way to the coffee pot.😁  

JD

Interesting thread and am guessing there is no right answer with many dependencies that range from equipment design to how often you listen. I keep mine on unless I know I am not going to be listening for a few days... My approach is based on this excerpt from my Lampizator DAC user manual:

"Power on-off cycle The tube lifetime, almost like the life of a car engine in cold climate – is determined largely by the on-off cycle. The heat expansion coefficient of the glass is so much different than that of the metal, that the air-tight seal of the metal pins can leak oxygen inside the tube and eventually kill it. Even if it is just one molecule per day. So in other words it is better to keep the DAC always on, than to switch it on and off more than necessary. The lampizator DAC with tube rectifier has a slow start feature which brings the high voltage supply gradually up, at the rate of two- to five volts per second. The PSU reaches 250 V DC after 90 seconds. This helps to extend tube life. The DAC is also equipped with voltage down feature (bleeders) which reduce the power voltage upon switch-off at roughly the same rate. On top of that – the tubes are operated always around 25% of full nominal power, which greatly increases their life expectancy. Combining all the factors together, the tube lifetime should be anywhere between 10 and 20 years, assuming the player is switched off only once per day, for the night."