carlsbad
1,213 posts
I’d say a very low percentage of tube amp users actually log hours. Most tubes are run to failure.
I'd say very few ARC Ref 6 run them to failure as the remote to the Ref 6 makes in incredibly easy to check tube hours. ARC does not make it clear in the manual but I believe someone reported here than when his 6550 arc'ed it took out a board. At 2000-2500 hours it ought to be replaced.