KT120 longevity

I've read 5000 hours.

I guess you will be the standard case to model future behavior on.

FWIW, I drive my ARC VS-115 with KT-120s. ARC still recommends replacement at 2000 hours. Do they have a longer life? Dunno. Maybe yes if you drive the tubes with quality electrons. I'd call the factory and ask the techies.

Tube amplifier manufacturers typically specify 2000 hours as the useful lifetime of these power tubes. It doesn't mean they suddenly drop dead after that, but performance degrades with more time.

Thanks for nothing my fellow tubeheads. I'm aware of Tube Death Theory but still wonder how long this particular tube type can continue before becoming land fill. Mine are still seemingly in the 4,750 hour break-in period. They're boring me with their longevity...they have lost nothing so I can't justify replacing them with new KT120 Cryoed Super Platinum Matched Quad ARC Factory Mermaid Drool Glass Polish Lubed Gold Pin Blessed by a Pope Hand Rolled Asteroid Mica Spacered Vintage Vacuum Sucked versions...thus robbing me, that's right, ME, of the simple guilty pleasure of tube rolling. Come on KT120s! Die bastards!...DIE!