[jonbee]

I've been all digital in my systems for many years now.  I've had at least 3 dozen coax, aes/ebu, toslink, usb, etc. cables. Initially skeptical about how much difference digital cables can make, as my systems have got higher rez, I found they really can screw up the sound in many ways. The last couple of years I've been enjoying the $500/m Wireworld Gold Starlight 7 AES/EBU and RCA, as being very clean and open. As non-digital sounding as I've run across.
My new Nuprime 10H dac/preamp doesn't have aes/ebu inputs, so I thought I'd try the top line $500 Acoustic Zen Absolute 75 RCA for a change.
Well, I'm glad I did. The AZ does everything the WW did, but does offer somewhat improved soundstage clarity and ambience. Not day and night better, and similar sounding overall, but they are now top of the heap in my world. Wonderful open transparency with low coloration and vanishing sonic artifacts.
I like the AZ so well I bought a second, one for my music server and one for my Oppo 103D video source. Same effect on both sources.
I moved both the WWs to my office system where they made a nice improvement there.
Both are highly recommended to provide non-digital sounding digital, with the edge going to the AZ in my system.     

[zoom25]

You might also want to play around with different lengths, specifically longer ones, as there is less reflectance. 

Reference: http://www.audiocircle.com/index.php?topic=140155.0

[jonbee]

After more careful listening and comparison, the AZ definitely outpoints previous fave Wireworld Gold Starlight 6/7 in top end definition and clarity, naturalness and soundstage ambience. Not day and night, but definitely better in my systems. I bought a 3rd AZ cable, and am now happily using them throughout my 2 main systems for my unbalanced digital connections.
One more step in the banishment of the dreaded digit-itis. Wonderful stuff.

[TJHUB]

Per John's recommendation (thanks again), I purchased an Absolute 75 for my system as well.  This cable is REALLY good in every way.  The clarity is just spectacular, and the best I've ever had.  It's everything John stated.