I have an amp that is a hybrid, It uses both sides of one small signal tube a 6DJ8 on the input (no need to match tubes) and the output uses power transistors. A ridiculously good sound. In this scenario the tube will and does last a very long time and the amp has been powered up 24/7 for best possible sound. Initially I have tube rolled with different brands that have produced dramatic results. It is nice to be able to tailor the sound for my speakers and for my own own tastes.
Disappointing short life of NOS preamp tube
Being sarcastic really.
I only got 7 years out of 50's 12au7 RCA black plate. That may indicate 5 more randomly futzing out the rest of this year.
With the state of tube pricing now, tubes definitely not on my list of unnecessary audiophool spending.
I was really hoping these things going for 20, especially them just being preamp tubes, not a power tube. Fortunately, I have one more for backup, plus the 6 stock tubes in the shoebox.
Such is life. I'm more impressed by my relatively quick troubleshooting, avoiding severe neurosis. Less than 5 minutes-patting myself on the back, and praise from the boss.
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