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.



In 2003 I ordered three NOS Mullard CV4003 (12AU7) for the preamp I was building. Average about 16 hours per week for roughly 16000 hours to date and still going strong. I tested all my tubes last month and these three still have close numbers. I have a backup set of Sylvanias that I'm not sure I'll even need in my lifetime. 😀

"It sounds like around 5,000 hours."

ghdprentice- I''m  thinking the tubes are now somewhere in the 5-7K zone, so yeah

I'm not surprised to see one futz out now. 

Anyone remember buying the 5 pack when they were "new?"