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mixing tubes and transistors

I'm considering getting a tube preamp in an otherwise all solid state system. The solid state gear is designed to be left on all the time. The tubes in the preamp wouldn't last very long if left powered up all the time. Here's my dilemma: the power amp owner's manual says to power down the components in sequence from the speakers "backward" to the source. The preamp is in the middle of this chain. If I turn off the preamp (to extend tube life) while leaving the amp and sources on (to keep the transistors thermo-electrically stable) am I creating any electrical hazards for my equipment? Please advise, and thanks.
prospersol7a6a
sean
6,231 posts
 
Leaving low level tubes turned on in standby mode is typically okay and recommended by several different manufacturers. My Father has been doing this for appr 15 years and only had to change tubes one time. Then again, if one uses "low grade" tubes or the component is not properly designed, you can expect significantly shorter lifespan than what he was been able to obtain with his. Sean
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bwhite
807 posts
 
Guess I'll through this in for thought... I believe it puts more shock on the tube component (lowering tube life) to power off and on frequently vs. just leaving it on.

Depending on the history of your tubes (new or NOS or USED), one can expect upwards of 10,000 hours in a preamp sometimes more. Of course as JC Audio mentioned above - this is not the case with ALL preamps and you should ask the manufacturer what he/she considers to be the average tube life in their product.
prospersol7a6a OP
1 posts
 
Thanks to all who responded -- it was very educational. The preamp I'm considering does in fact have a standby mode, so I'm going to leave it powered up as several of you suggested.
sugarbrie
3,854 posts
 
10,000 hours is about 415 days. If you leave tube stuff on you're replacing tubes every 14 months by that estimate.
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