USB DAC of Oppo 205

dbphd,

Were you planning to get the NAD possibly  to support subwoofer integration or for a surround system?  Because for stereo, it seems  you are one repair away from being back in good shape.

I have the Ayre QB-9 DSD and Ayre AX-7E as components in my secondary system as well.  So you are already experienced with the synergy and SQ with this pairing. It must also be great with your KEF LS 50's.  (I'm feeding a set of Triangle Comete's).  I'll spare you a long litany of reasons why IMO a NAD M-22 will not come close to what you were hearing from the AX-7E, and end up costing more.  

But I highly recommend that you give a phone call to Ayre Acoustics for two reasons: a) to discuss repair options, and b) to let them explain the very straightforward solutions for running subs along with the AX-7E.

As an aside, Ayre customer service is first rate, and they provide repair  support  for all of their components, no matter how old.

So,  2nd system setup might be:  Oppo 205 streaming/CD, etc.  out to Ayre QB-9 via asynchronous USB. ( A/B test Oppo DAC against QB-9). Then, fully balanced discrete XLR connectors to AX-7E with feeds to Velodynes and Kef's?

There's nothing quite like preaching to the choir, right?  You also seem to have everything you need to evaluate the Oppo DAC performance in your system.   

Maybe worth mentioning the (long?) pending release of Ayre CX-8 as interesting comparison with your C-5XE MP.