New amp for Vandersteen 2CE


Hoping you can help me narrow down my choices for a new amp for my Vandersteen 2CE speakers.  I have been using a pair of Adcom GFA565 monoblocks.  They have ridiculous amounts of power, but I don't come anywhere near using it all and I would like a little more clarity in the midrange.  I have two used amps I'm considering - a McCormack DNA 0.5 and a Pass Labs Aleph 5.  Another option would be a fully restored/upgraded Adcom 535/545/555.  Source is a Sonos Connect with a passive attenuator for volume control.
Thanks for the help!
craig2112
I found significant improvement in my Connect with Parasound Zdac and Peachtree Dac itx - relatively low cost improvements - but if you are happy with it as is...
If you're staying solid state, the Pass would be my first recommendation.

But the 2CEs work really well with tube amplifiers (we have a lot of customers using them), and if you "would like a little more clarity in the midrange" as you put it a tube amplifier is going to be a no-brainer for this speaker. You will need at least 60 watts in most rooms. 
Thanks Atmasphere. I have tube guitar amps, but haven’t gone to tubes in my audio system. For now exposed tubes seem like a problem waiting to happen - kids.