I've seen good things about Abyss, but way out of my price range. You add proper DACs and amps on top and you're talking about $10,000, if not more. The Noble Khan I've heard negative things about. Hoping the HD820 would be a good compromise, and disagree on an implication of overly wide and exaggerated soundstages. The Sennheiser HD8**s have much bigger issues than that silly accusation in my opinion. I didn't even find the HD800S that wide, the separation is what stood out. But it was very dry with awful vocals, not to mention something about what I was using made my ears ring very quickly. It was unfortunately a no-brainer return vs an Audeze LCD-X, which eventually was a no-brainer sale vs the HD650, and that's what I was left with.