How can do you extend the life of your tubes?


My amp premp and cdp are tubes. I read years ago, proportionatley, the most tube wears comes from powering up. And shutting down, and then powering up shortly is life shortener for sure. Shortly is too vauge. What do you tubers do to lenghten the life of your tubes, especially when we're talkng NOS and the like? thanks in advance.
128x128warrenh
02-16-13: Warrenh
how do you know your tubes are beginning to fail and your music is suffering from tube deteriration?

Generally, again reffering to light bulbs, tubes either are working or not working. You will hear failure as buzzing, becoming microphonic (hearing footfalls amplified), or some other audible clue. This is unlike cartridge wear, in my experiences. While a cartridge can slowly degrade over time, the tube's decline will be rather sudden. It will sound fine one day and then the next day you'll notice a buzz or hum being generated. Then you'll have to track it down to a specific tube.

Do you bring you little babies to the tube Doctor to be tested?

No, once an audible issue has been diagnosed in a tube, the doctor's equipment cannot save it, so why bother testing it?

Also, when one of my driver tubes goes, time to replace all of them?

You can, and many people do, but you don't have to. I would say it depends on the age of the tubes. If I've had the amp for 3-5 years, and one driver tube goes, I would probably replace them all. However, if the tubes are only a few months old, I would probably just replace the defective one. Again, think of light bulbs. Let's look at a chandelier, if one bulb goes, do you replace them all? I have a chandelier with 6 bulbs, recently 3 bulbs died within a 1 month span. I changed them one at a time. Should I have just changed all 6 at once, maybe. That's a personal issue that will depend on your own personal comfort level, OCD level and financial situation.
Ghosthouse,
My Hickok 539C does have provisions for a "Life Test". This setting reduces the filament voltage by 10%. In this setting the mutual conductance is not supposed to drop more than 20% compared to the "normal" setting.
I'm no expert here, and can't confirm the accuracy, but it sounds like this is what you're looking for in a tester.
Thanks, Mark. Helpful info. The other thing I was hoping to be able to do was match tubes so if I had a group of, say, EL34s of the same brand but with different histories, be able to put together a quad that could be managed by my amp's auto-bias circuit. I believe if tubes are too mis-matched auto-bias can't compensate...apparently not good for the amp. Is matching something a tube-tester can be used for?? Happy to be corrected on this issue.

Warren - apologies for hijacking but hopefully this is at least somewhat related to your question; that is, having a reliable piece of test gear would keep you from unnecessarily tossing tubes that still have some life in 'em (assuming no audible degradation in sound quality).
Thanks Jmcgrogan2 & Elizabeth for the lessons and clarification. It is appreciated.