There are so many...
But definitely check out Imogen Heap. Song Hide & Seek on Album Speak for Yourself. Crazy vocal effects, but beautifully produced.
I am not a gear-geek nor an audiophile, but FWIW I have two albums that sprang to mind instantly when I read the question:
Sade - Promise (I have this on vinyl - simply amazing)
A Perferct Circle - Mer de Noms (the louder the better)
Of course, in a completely different interpretation of the question, I might also pick The Trinity Session by Cowboy Junkies... total goosebumps.
Rest assured I will be making an effort to listen to some of the previous suggestions!
"Nickel Creek. The vocal blend is foremost, but also the clarity and depth of the each instrument is among the best I'm aware of."