Pre-amp for my Ayre V-6x - K-5x or JR Concerto

Has anyone tested the new Jeff Rowland Concerto pre-amp ?
I am looking for a pre-amp for my Ayre V-6x amp and hesitating to buy the Ayre K-5x.
Not that a preamp has anything whatever to do with other components, but the entire JR line is among the few components with excellent specs.

His amps are comparable to the Hafler DH-200/220 ($200), Muse 160 ($7-1400); ATI ($500-$)2k; the also pricy Bryson, for instance, but none meets the JR aesthetic standard.

One model is so beautiful that it comes with an opitonal clear plastic cover to reveal its interior. You could hang it on the wall. Really.

And of course the vintage Haflers are light on build quality. I think ATI is the best value with no performance/build quality compromise.

I personally use a digital processer (Lexicon DC2) instead. Its AD/DA converts the Digital Out of a CD player to 24bit. No more concern over whether there is any actual value in the higher cost new bit rate technologies of CD's, though at best the result is subtle.

Better to work on the transparency of speakers, their setup, and a distortion free amp. The other components become less signifant as a possible solution to poor performance of the system/room.

Though the source material does become more of an issue then. Since you can hear with a significantly higher degree of accuracy its true sonic characteristics: the good, the bad, and the ugly.

So, some in your collection will become intolerable, while others will sound even better, and you will hear things that you had not even heard before.

Realism. So much better than using a system to attain some subjective sonic quality or other of its own that results in a kind of sameness with all recordings. Having masked them with a favorite distortion in this component, and yet another in that one.

The truth will always be superior to fiction.

Check out a knowledge base of truth in all things audio. BTW there is also a list of tested and proven well produced and engineered sonically superior reference quality CD's in a variety of genres at the MUSIC link.