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Leave tube amp on all day?

I've just purchased my first piece of tube gear, a Cary SLI-80 integrated. What's the best for tube life? Leave it on all day or turn it on only when it's used?

On days I'm home, I may listen an hour in the morning and a couple hours in the evening. If I leave it on all day, to get 2-3 hours of listening time, it'll be on for 12+ hours. This means the power tubes won't last more than a year? If I turn it on and off 2 to 3 times each day, will the tubes last longer?

If it's best to just leave it on all day, then is it advisable to leave it on over night as well for multiple days? Turn on Friday evening and turn off Sunday evening?
in_power2002
eldartford
4,262 posts
 
Some tube equipment has a mode where only the filiaments are left energized, perhaps at slightly reduced voltage. It is always desirable to turn on filiaments before gradually bringing up plate voltage, but I don't know any audio amps that are this sophisticated.
czbbcl's avatar
czbbcl
1,752 posts
 
mapleleafs3

Better to be safe than sorry. But then again that is just my opinion.

Chuck
in_power2002 OP
6 posts
 
Thanks all for your responses. Looks like turning on/off the amp 2-3 times on days I'm home won't shorten tube life more than leaving it on all day from what I gather here. At least that saves on electricity.

I wish there was a standby switch on this amp, as I would use it but unfortunately, it's just on or off.

Tube shorting? Ouch. It never occurred to me that was even a possibility. The amp has fuses, so I assume that would go before there's a fire hazard? Man, don't tell me everyone who has tube gear has a fire extinguisher next to their equipment rack. :-)
cruz123
586 posts
 
Welcome to the SLI-80 club. Its a great amp. If you search the FAQ's at Cary's website (CaryAudio.com), they offer their advice on this issue. My recollection, in a nutshell, is that Cary advises to turn the amp off if you plan to go more than a few hours without listening. On CDP's, they suggest leaving them on 24/7. I find that the amp heats up pretty quickly and I haven't noticed any significant improvement in leaving it on for long periods. So I just turn the amp on as needed. My CDP (Cary 308T), on the other hand, seems to benefit from being left on. I usually compromise and turn on my CDP on Friday evening and leave it on through Sunday evening, since I do most of my listening on weekends. During the week I turn both the amp and CDP on as needed.

Enjoy the amp!
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