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Tube Life Question: 12AX7 Drivers

Hello.

OK, here's a question for some of those out there who have lived with 12AX7 drivers. How long have they lasted in your experience? I used to have an amp that used them, and after 6 years, they still seemed fine. Now that I again own an amp that uses these tubes in this application, I'm wondering what the actual life expectancy is - 5 years, 10 years, 25 years???

Thank you in advance,
Joe
trelja

Showing 1 response by atmasphere

atmasphere's avatar
atmasphere
11,632 posts
 
Hi Joe- 12AX7s can't make a lot of current, which usually means they get voltage amplifier service in a power amplifier. Using them as a driver tube is quite unusual. I take it the amp is Class A? That would be about the only type of service that a 12AX7 would work for.

Delayed B+ voltage on warmup will also help prolong the life of the tube. You might look into adding this feature if it is not already on the amp.
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