How can do you extend the life of your tubes?

I have read slightly under-biasing the output tubes will extend the life. Does it affect the sound? Yes in my opinion. That being said with most of my tubes I have to 'squint' to hear it. Another thing when the unit powers up you should let the tubes 'bias up' before playing music. I have found with under biasing the tubes it generally takes 2 to 3 min to bias up and when biased to spec it may take 5 - 7 min. Anyhow that's the routine I go through. My integrated is an Octave V70se which has standby and soft start. Soft start turns on the input and driver tubes first and about 20 sec later it turns on the output tubes.

thanks guys...I'm doing the same. Now how about this:
how do you know your tubes are beginning to fail and your music is suffering from tube deteriration? Do you bring you little babies to the tube Doctor to be tested? I would not know what to listen for. Also, when one of my driver tubes goes, time to replace all of them? I started a new thread on this to get some additional action. Thanks again.

Great follow up question, Warrenh. I'd wanted to get a tube tester and did talk do a couple of electronics techs with units for sale. Those discussions were not real helpful. They were very non-commital on whether a tester (and talking some of the better regarded vintage units...think Hickok) would do what I was hoping; i.e., warn of a tube going bad or that needed replacing. Kind of left me scratching my head and I never did invest in a primo tester as a result. I guess I could ask the audio dealer I've done business with to test them on his unit for a fee.

Hello Warren,I would have a new set of tubes on hand .You can compare the
sound quality between the old and new to give you an idea how worn your tubes
are.Also to get an idea what is changing as the tubes age.I ve noticed in guitar
amps that the sound gets duller,less vibrant as they age .Kind of like a set of
guitar strings getting old and flat sounding.You can also keep a set of old tubes
to remind you how much better your amp is sounding with the new,or newer
tubes.Ive noticed some of the worn tubes seem to lose some volume as well.

Since we're only talking about non-power tubes, then neither of your questions should be a source of worry. Leave the tubes powered 24/7 and change them at fixed intervals. It could be every 6 months or 2-3 years. A very small number of vendors are selling truly unused NOS tubes, most are used, even when stated otherwise. If you're not hearing any distortion or gain imbalances, then don't worry about it.