First Test for tube bias on ARC Ref 110?

It's surprising that Reference models of ARC do not have an auto-bias. Even if the most primitive autobias circuit is implemented, you don't have to worry about biasing for at least half of tube life. I don't clearly understand ARC philosophy beyond that.

The ARC sound is highly resolved, open and transparent. Any additional circuitry that does not advance those goals (or worse yet that detracts from those goals) is not included in their designs. Convenience vs. sound quality I guess is at the core of their thinking. That is my best guess at their thinking.

I would check the tubes to see if they have drifted a bit. Then I would check them maybe around a hundred hours.

I also own a Ref 110 but I don't use ARC tubes. ARC burns their tubes in a bit before they are matched. This tends to make the matches much better than tubes that are factory matched. The Ref 110 is an excellent amp. I have owned mine for a few years now and it never ceases to amaze me.

Convenience vs. sound quality I guess is at the core of their thinking. That is my best guess at their thinking.

It's the best phrase to cut corners, but reality is different.

It's the best phrase to cut corners, but reality is different.

I am not sure I follow your logic. Why is the exclusion of a self-biasing circuit cutting corners, if your primary goal is to produce superlative sound from your products and if you believe that the inclusion of a self-biasing circuit takes away from your goal of producing superlative sound. I am not sure I follow Marakanetz.

inclusion of self-biasing circuit only improves sound.