The Reference Two's are really quite different from its predecessor the Reference Ones. The input board has been modified changing the 6SL7 input tube's configuration. The power supply has also been updated making the overall noise floor lower, much lower. The output transformers also a wound a little different giving a much wider, deeper sound stage along with improved micro and general dynamics. I have heard both the Ref One's and Ref's Two and the latter simply blows away the Ref One's, and I thought the Ref Ones were unbeatable!
-Ron
-Ron