I spent about 5 minutes on the WA22, which surprisingly did nothing for me with any of the cans I listened to, and a few short seconds with the ZDT, which sounded really lovely. It wasn't euphonic or syrupy or slow, it was just powerful. Dynamics were really effortless, in my short demo, and that's a very good sound.
I suspect the WA22 wasn't entirely to blame, but rather the Northstar CDP connected to it. Also, I imagine the fact that I wore an ill-fitting pair of Qualias contributed more than either of those Something in that system didn't quite gel for me. I'd love to hear the WA22 in another setting sometime, as it was a really beautiful amp.