What is the VERY BEST CD album you've ever heard?

Donald Fagen “ The Nightfly “ and Andreas Vollenweider “ Book of Roses”

Wow that's hard but I have a few that are the best sounding in CD format.

Eva Cassidy "Nightbird" 

Palladin Ensemble "An Excess of Pleasure" on Linn label.

Jennifer Warnes " Famous Blue Raincoat"

Not sure if these are the best streaming selections and definitely NOT in my top tier of Vinyl releases. 

The Collected History of La Scala.

Great and timely post as recently been organizing/cataloging my CD collection: 

Kiri Te Kanawa: "Mozart Opera Arias", London Symphony

Buena Vista Social Club (one of several CD's produced by Ry Cooder I love)

Ry Cooder "Jazz", "Paradise and Lunch", etc.

Gary Burton: "Reunion"

Paul Michael Meredith: "The Luxury of Love"

Beck - Sea Change.   Mofi special limited edition CD.  Beck at its best, for me.