I have owned a Ref 3 for a couple of years. The lifespan estimates made by ARC for all tubes as applied in this device are extremely optimistic. The 6550C shows some sag at 900 hrs and usually needs to be replaced by 1100. In my unit the driver tubes had lost their bounce by 1700 hrs. I have tried a couple of different tube variants, but prefer the transparency/clarity/linearity/detail of 6550C and 6H30s supplied by ARC. You will find a good discussion on 6550C alternatives here:
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1201144495&openfrom&1&4#1
Before any serious evaluation of your Ref 3, give it fresh tubes and break them in for 100 hrs or so.
G.
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1201144495&openfrom&1&4#1
Before any serious evaluation of your Ref 3, give it fresh tubes and break them in for 100 hrs or so.
G.