Jazz vocalists which may not be as real as we think/imagine

Sure we could include all genres of vocalists,  but lets focus on jazz performers,,for instance , take Diana Krall. 
I have a  pile of cds that i do not listen to, old rock,,, 2 are my wife's she picked up as gifts, and never listened.
So I figured maybe I can use DK's as a  test reference recording.
Her 1999 and 2001, both seem to my ears her voice is somehow ~~tweeked~~ laid out with modern aids such as EQ's and such.
My Q is , can we really consider DK's voice to be The Real Deal,,, or a  perhaps a toch of  ~ The Fake if not perhaps, bordering on, fraud. 
I really can not use her cds in my testing of new tweeks, mods, , Her voice comes across wayyyy too warm = Colored = a nono for my ears. 
I am after pure cold frigid, icy clean mountain spring water. 
Anyway, justa  random thought,, what say ye? Have you noticed this quirk among other jazz performers such as Sophie Milman, which btw , i do use in  my YT vid uploads of testing reference on tweeks/mods/upgrades. 
Her voice is at least somewhat more~~ a  natural~, Just barely,,had her engineers gonea  tad too far in tweeking, I may have to  also disreagrd her cds. 
Sure you might object and claim all recordings post 1985, have these intrusions of tweeking /EQing the voice, as a  makeover. 
I don't know, maybe in the past 20 yrs things have gotten out of hand. 
So cast your vote, is DK's voice real deal,, or a  tad fake?
Can she perform unpluged as she does on high tech studio records?