Between my tubed CDP and integrated tube amp (i.e. I only need the one pair of IC's), I first used the WOW, then upgraded to the Matrix Ref II, and now the Silver Reference II. The Matrix Ref II and Siver Ref II are much better that the WOW in my opinion (with the Silver being the better of the two). As previously recommended, for about the same ultimate cost - I would prefer two Matrix II's over a combo of the WOW and a Silver Ref II.
