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Is it a OK to leave tube pre-amps powede up 24/7

I’m relatively new to tubes in my hifi setup. Recently went from SS pre to tube ARC pre-amp and a Croft phono stage.

I have always kept all of my SS gear powered up 24/7(and still do), but I shut down my pre-amp and phono stage now after I am done listening for the day. I power them up at least a half of an hour before I put anything into play.

I would prefer to leave my tube gear on all the time, but am concerned about premature tube wear.

What would the tube folk here think about 24/7?

128x128crazyeddy
czarivey
5,946 posts
 
Well, some  ARC tube preamps can power up a pair of small speakers if connected to the output to significant SPL levels.
That is to say that signal tubes there are driven rough almost just like power tubes.
PCB might not catch fire, but it might burn 'foil side' that in places will need to be either rebuilt or point-to-point wired. 
Once again, the possibility of failed signal tube to affect other circuit components as well as PCB is there.
crazyeddy's avatar
crazyeddy OP
381 posts
 

Thanks for all the comments from both sides of the question.

I have left them on for the past few days, but I think I will revert to the way I was doing things before. Power up 30 minutes before listening.

Since I have been leaving them on, and away at work during the day, I have a constant nagging feeling about them being "live" while there is nobody at home. Piece of mind is going to out weigh any sonic advantages.

Thanks once again everybody

sebrof's avatar
sebrof
835 posts
 
Cant's tubes short, and even explode? Is it wise to leave them on if you are not around to leap up and turn the system off?
Well if they're gonna explode I'm not gonna turn 'em on when I'm in the room!!
noromance's avatar
noromance
9,773 posts
 
I have seen a few tubes go out with a bang but never explode.
My TVA-1 used to destroy Mullard Osram KT88s - plate red hot and some sparks then a fizzle and a pop from the speakers!
czarivey
5,946 posts
 
Folks,

It's not even about tubes, It's about TEMPERATURE and the length of exposure to such temperatures. Speaking of ARC tube preamps YES they run hot! A faulty DC capacitor can cause excessive bias current and destructive heat that can cause PCB go to flames. 

As I've mentioned prior, one is too many, but repaired more than one. Running units 24/7 in simple term mean you don't give your circuit elements a 'recoil' time to recover after applied heat. Shortening life and paying extra for the idle time. That's where simple math shoves all the science behind.
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