First Test for tube bias on ARC Ref 110?

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!

Cmalak,
Why do you thing that it's done by "added microprocessors and digital circuitry"?
1. Autobiasing is done in DC domain and does not affect the signal no matter what kind of components are being used vacuum, solid-state or ICs.
2. Autobiasing could also be done without using any "added microprocessors and digital circuitry" by common cathode resistor(1940's?), but modern means of autobias widely implemented in Quicksilver amplifiers not only save tube life, but apperently improve sound! Stable quiescent grid current is a "dream:" of every tube push-pull amp.
Pardon, but I don't see this as convenience only feature.

Marakanetz...I guess we will just agree to disagree.

Yup,
Why not? Autobias will substantially decrease tube demand on the market. Microstrip speaks nothing but the standard marketting words to make an amp cheaper.
How much the price of the unit will increase by introducing common Cathode resistor or few semiconductor elements(modern way)?
This makes the unit plug-n-play with bullet-proof reliability that substantially decreases demand to send the unit for repair.
I explained facts and not opinions or judgements.
For next upgrade try to get Quicksilver's flagship and experience the magic along with bullet-proof reliability.

Marakanetz...Thank you for your reco of the Quicksilver amps but I am very happy with my crappy ARC Ref 110. It offers horrible sound performance because it does not have an auto bias circuit. But I guess I will just have to do without it. The Ref 110 has gotten awful reviews and 0 awards from all the various audio publications. It is clear to me now that it has to be the absence of an auto bias circuit that explains it all. Oh yes, ARC was trying to save a couple of hundred dollars on a $11K unit because they are in the habit of cutting corners. Their audio engineers are amateurs and they have no clue.

All the best.