Sean, you hit the nail squarely on the head. Not all material is as cleanly recorded as Levinsons Red Rose sacd. The breathy sax, the airy voices, the strings...masterful and engaging. The orchestral tracks in The Little Mermaid show off dynamics and soundstage to a fare-thee-well.
When I put on Mark OConnors 'Heroes' (and other cd and/or vinyl) and all I can think about is 'how poorly recorded' some of these tracks are, it really can get in the way of enjoying the musical intention these folks laid down.
My thought in stepping up to the 'tube plate' was based on sweetening up the system a bit, and getting back to enjoying the music. If a touch of accuracy and dynamics are lost, so be it. If it 'distorts' the recording in a positive way, that could be just peachy. If it's 'real music' and I get sucked into the performance, it will be worth it.
I guess it's feeble attempt (or a copout?) on the path of upgradeitis. I am trying to avoid replacing every cable and component in this digital system two or three times in the chase for the sweet sound of tubes. Basically just skipping the middleman and heading straight for the glow of valves. If it doesn't work out, well, back to the drawing board.
I'ts funny, I don't remember having any trouble at all with my old tube stuff, tho the S.C. did cook a capacitor once that I easily replaced. Memory is a funny thing, and maybe I'm not remembering the sweet sound of tubes at all... but the smell of Grandma's pot roast! ;-)