First Test for tube bias on ARC Ref 110?

The amp is brand new and the tubes are the KT-120's included from ARC. Sounds like I should probably start checking them now. They have about 54 hours on them at this point. Thanks for the feedback.

I have to agree that auto bias is a very convenient feature, but I think it slightly hampers overall transparency. I have also owned the Primaluna Prologue Two and then upgraded to the Dialogue Two (both with KT-88's) and both are lovely amplifiers for the money involved, but after comparing to others in relatively similiar price ranges (Rogue, ARC's integrated) I could definitely hear a more transparent sound in those without auto bias. These differences could potentially be many other things, but on first glance, that is my assumption as to what differs between them electronically. This is not meant to put down Primaluna in the least, again, they are great amps, though I think you pay a small price for the ease of use with auto bias.

70 total hours of running in so far, I just checked tube bias for the first time on my Ref 110 and three of the four sets were running just a little bit low. Should be at .65mv according to ARC manual and they were running around .61-63mv. I assume this is a very minor/mild drift. I adjusted the three sets that were slightly low back up to .65mv and away we go... I will check again at 100 hours. This was my first time biasing an amp, and I found it to be kinda fun!