Yes, KT66. I'll ask more about specifics later, when something concrete has been sealed.
So to complete my raising of balanced vs. unbalanced, I finally stumbled on the pair of Cardas XLR/RCA adapters I'd been looking for. So with my Directstream feeding ATC's, I went back and forth between the RCA and XLR outputs, playing several flac music files of various types, using the Decibel X Pro app with an iPad to control for volume level as best as possible. The result, even with only a 1.5m run, was immediately noticeable. The RCA was thinner and thus clearer in that way, at times feeling a little sedate, while the XLR had much more body, air and felt more dynamic, swinging. Not a perfect test because of the adapters, but the best I could do. Too bad, because the balanced upgrade is an extra big bill.