Reliabilty, Keeping Equipment Powered on or off?


I generally keep my system components powered on because the system does not have to "warm-up" when I sit down for a listen. I do know that reliability is usually calculated by POH (power on hours) however this calculation IMHO is a broad brush stroke. I do power down certain components that are not required to be left on to sound their best, such as a Luxman T-117 tuner and Wadia 171i Dock . However, my Krell IA, with the volume turned all the way down runs pretty hot, so hot you can't leave your hand on it. When turning the volume up on the Krell to reproduce the live event sound level, you can fry an egg on it, so I can only guess the Krell was designed to handle this kind of heat? However, back to the other components, such as DAC, SACDP, Headphone Amp, etc. Is keeping everything turned on asking for trouble or is leaving it on best to prevent thermal expansion and contraction which may be detrimental?
grm
I don't know if it's true, but I've heard that one should keep their tuner on, even when not actively used while otherwise using their system.
Perhaps some one with more definitive knowledge can chime in?
As Gdhal indicated this question has been discussed in a number of past threads, with lots of opinions being expressed but without much in the way of consensus being reached.  IMO all that can be said with confidence is that it depends on the specific designs that are involved, and on the usage patterns of the particular user.  And on the particular user's feelings about energy conservation, especially with respect to components that consume a lot of power.

One thing you might consider doing, if no guidance on this issue is provided in the manuals for your specific components, is asking the manufacturers of the specific components for their thoughts on the matter, while describing your typical usage patterns to them.

Regards,
-- Al
 
The manufacturer of my amplifier (Odyssey) recommends the amp stay on at all times unless you won't be using it for months on end.  My Stratos amp has been left on since April 2010 and only turned off for 10 days when we went on a long road trip.  My amp has always worked flawlessly and is never warm when idling or being run hard.
Hi, and thank you!

After digesting the posts above, I will be powering everything down with the exception of the Krell. The Krell sounds best when left on and I do not want to introduce thermal stress on the 24 output devices, i.e, cold to hot, hot to cold, etc. I think for this amp, leaving it on with the output devices "warm" is the best way to treat them?

Thanks to all,
grm

From the standpoint of safety, longevity and energy savings, it makes sense to power down everything.  This is particularly true of tube gear.  I can understand not wanting to power down amps which can take a really long time to come back up to song, but, these are exposed to the most heat from being left on, and these can do damage to speakers if something happens while you are not there to power them down.  As for thermal cycling, that is really not an issue because it happens relatively slowly.  If you look at rating of most parts, they include rating by operating temperature--the higher the temperature the shorter the life.

I only keep on what is meant to be on all the time.  That means I don't power down my music server/NAS.  It would take about 20 minutes to bring the server network back up if I turned it off (components have to be brought up in a particular sequence).