Thanks, gentleman. Sage advice. I qualify my comments with great in comparison to the B&Ws. I suspect there is more, particularly on the low end, than my amp delivers.
Or maybe it is just the Thiels expose the limitations of my upstream gear (Rega P1) and (Sony SACD CE595, budget SACD multidisc that has gotten some bang for buck praise).
I have little to quibble with on analog side but some hit and miss with CDs that suddenly sound thin. Clearly, the speakers do expose poor recordings, too, because same songs on different CDs can sound quite different. May I ought to be looking to upgrade CD first.
To confess, the real problem is I have more than offset the cost of Thiels by selling my old stuff (stunning what used Bang & Olufsen cartridges fetch on ebay) so I am surprisingly sitting on a bit of cash and trying to figure best places to start a slow upgrade of rest of system. The amps, from reading other Thiel discussions, sounded like a good start.
I'm gonna think on it a bit.