Amp for Acoustic Zen Crescendo 2 ?


Hello all,
I have these speakers for 2 months now and want to move on to a tube amp of 50 - 60 wpc or so, or a SS amp that fits the bill..  My current amp is an Ayre V-5xe.  I'm looking for an amp to sweeten up the top end and has a midrange that does vocals full and articulate, even if that means colored.  The Ayre is a great amp but I think there is a better match out there.  I'll have to save up for used, under $5K.  I'm especially interested with what actual owners would say, as well as their system specifics, but all comments welcome.  Acoustics and speaker placement are fixed and substandard.  That's just the way it goes at our house.
I'm using a steel arm VPI TT with Ortofon Cadenza Bronze, ARC PH-7 and REF 3.  Thanks.

wlutke
i was going to say contact www.audiothesis.com (the mastersound distributor) he has a trade in at a great price.i own one powering a pair of rosso fiorentino volterra speakers 87 db 6 ohm(3ohm min) and the sound is to die for.

but he has purchased the pass labs.
@grannyring
"I will add everyone should bypass their speaker binding posts for better sound."
I have Acoustic Zen Adagios Jrs.  I pulled out the rear plate with the speaker binding posts and jury-rigged the speaker cables directly to the internal wiring.   Wow!   The resolution increased substantially.  Much deeper soundstage. Lost some warmth - which apparently was signal degradation via the posts.   It's almost like they're new speakers.   Thx for the suggestion!  

Wouldn't it be great if speaker manufacturers extended the internal wiring through cabinet - on to the posts, so that the speaker cable spades could make physical contact.  It would be a cheap, but significant upgrade.  I suspect that the quality of speaker binding posts is a price-point decision.  How many manufacturers actually take into account how the binding posts affect the sound?  As far as I know, Wilson Audio is one of the few.