Fortunate that your pre is not pushing tubes hard, considering also the on off cycle.
Sad moment when they go and wonder if the new pair will sound the same.
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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