ARC ref 210 vs ref 150

Mickey, you wrote "[w]ith regards to the pre, it needs to be matched with an amp with a fairly high input impedance. The Ref 150 SE is listed on the ARC website as having one of 300 kOhms and that should be sufficient. Is that the same with the Ref 150?"

The answer is yes. The specs between the Ref 150 and 150 SE are almost identical. Ditto the GS 150. You should note that the Ref 150 (SE and non-SE) and GS 150 only have XLR inputs ... no RCA/SE jacks.

The Ayres were very very good. They were not quite as powerful on the bottom end as the Dags.
But the difference between the Ayres and the ARC was simply the difference between excellent tubes and excellent solid state. Better bloom, 3d presentation and palpable images from ARC. Slightly greater transparency from Ayre. In many other areas, they were virtually indistinguishable.
I am a tube fan. So, for me a great tube presentation beats a great ss presentation.
A ss guy will prefer the Ayres.

I think I would prefer the ARC too.

Thanks that was very helpful.

I recently took my Ref 75, which I had retubed with KT 150's, back to the dealer for upgrade to SE status. Fortunately, the distributor OK'd doing the SE upgrade without the cost of new ARC 150's. I was able to compare my Ref 75 with KT150's, with the dealers 75 SE. I can confirm that the SE upgrade to new capacitors etc, gave a similar increase in performance, to the KT 150 retubing. My original thought was most of the performance improvement was in the tubes, not the other changes in the SE upgrade. This, to my ears, appears not to be the case and you need the full SE upgrade package, to get all the benefit out of the 150 tubes.