New amp for Vandersteen 2CE

Why buy used?
http://www.odysseyaudio.com/products-khartago-stereo.html
or this
http://www.avahifi.com/index.php?option=com_content&view=article&id=169&Itemid=254

Build quality is better on the McCormack and Pass Labs, but you have a good point on Odyssey.  They are getting good reviews though I have never tried one.

As a McCormack fan, I would normally say go with McC.
But, as you have the Adcoms, why not upgrade them at MusicalDesign and see if you like them?
I had the Adcom 555 running while my DNA-1 was being upgraded by SMc. When the DNA came back, I was very pleased, but I have to say that old 555 really held its' ground for a 35 year old machine. As you say, the Adcom is kind of rough around the edges, so when I asked Musical Design about the upgrades, he said it gave it more smoothness to the midrange.
For the 555, it was quoted around $300, for the 565, probably a little more. But, that's alot less than the $1800 I paid to upgrade the DNA-1.
You haven't mentioned your interconnects. Those can make a big difference in the midrange, as well.

Thanks, really appreciate the McC and Adcom comparison.  Since the 565 are a pair, upgrading does start to add up, and the cost is pretty similar to a DNA 0.5.

I build my own interconnects using teflon or foamed PE shielded cable.

Once owned a pair of 2CE's and should have kept them. I had the beige socks which looked nice... also had the Sound Anchor stands which are a must. All the amps you mentioned are good amps and I've heard them all except the Odyssey. I wouldn't spend the money to upgrade your 565's; no doubt the Musical Concept mods will improve them... they're good mods. The fact as you mentioned you don't need the power and as you describe them is accurate with the Adcom amps. Adcom's were great bang for the buck and yes Musical Concept or Design mods were very popular back then. 

I I haven't heard the odyssey amps but they get great press and a lot of people hear throw them out so hopefully they really own them or have spent time listening to them.

Between Adcom, McCormack DNA 0.5 and the Pass A5 it's definitely the Pass with you speakers and what you are looking for. If the DNA 0.5 was a Deluxe I'd still go for the Pass. If you needed the more flexible amp and was set on the DNA 0.5 look for a Deluxe as it is a much better amp than the standard one. 

The Pass Aleph 5 is a very nice amp and on many speakers it's not the ideal amp but it will work nicely on your Vandies. It is a little toaster as you probably already know. If you don't like it, it will be an easy sell.

the Sonos has a great user interface but a poor quality DAC

I second the Odyssey.  Although I no longer own Vandys, I had a pair of 1Cs when I first bought my Odyssey Audio Stratos HT3 (with cap upgrade).  This is a very good amplifer with smooth, detailed highs that helped take some of the edge off the Vandersteen metal dome tweeter in the 1C, which I found somewhat etched and grainy.  Look around for reviews on the Odyssey amps, I think you will get the impression they are worth a try.  Sold direct with a 30 day return option.

adg101 - thanks, I'm strongly considering the Aleph 5 despite a form factor that will be difficult to integrate, a power switch buried on the back, and the fact that it is a "toaster"! 

jl35 - poor quality DAC is overstating it a bit.  My experience is the DAC is capable enough.  Next project will be to try out several external DACs, but this is an area of high cost and diminishing returns.

bondmanp - I've done some digging and Odyssey sure does get some love, so well worth considering.

So really it comes down to putting some money down and trying some things out.  These all seem like really good options.

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...

hey, if I was happy as-is, we wouldn't be talking :) 

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.

Rotel is a nice match for Vandy speakers.

CJ tube amp with a cage..nearly kid proof...
the Khtargo does work very well w Vandy..Brother in law running that w Candela pre and Bluesound streamer/ DAC.

craig2112, 
if you are going to stick with solid-state, my recommendation would be to stick with a bipolar (BJT) output stage power amp (like the DNA 0.5 you have in your list). 
I see that you've been listening to a BJT output stage power amp (your Adcom GFAxxx) all this while & staying with that topology would be recommended. I think that BJT output stage power amps sound better than MOSFET (NOT intending to start a BJT vs MOSFET argument) but then each listener has their own preference. I think that BJTs are a much better current source (which is basically what an amplifier output stage is) & since BJTs have higher gain, fewer stages (less distortion & less noise) are required for a high(er) current power amp. 
Looking at the impedance & phase plot

http://www.stereophile.com/content/vandersteen-2ce-signature-loudspeaker-measurements#9XpubygHe0pY1BVW.97

the speaker is a fairly benign load (I can see why Atma-sphere says that a lot of his customers use his OTL power amp with this speaker) but it is mildly taxing to the power amp hence ensuring that your new power amp has sufficient current at 4 Ohms (for the bass region where the speaker impedance is 4 Ohms & phase angle is mildly inductive & mostly capacitive) would be a good idea. 

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.

I've seen comments like this a fair number of times in the last 40 years. It does make me wonder how we humans made it through back when tubes were the only game in town! So far as I have been able to determine, as far as kids go, tubes are not any bigger deal than a turntable or CD player.

I don't think an amplifier change will give you what you're looking for. If you decide to go that route, try before you buy.

I hear that Ayre Acoustic V5-xe is great match for those by coincidence I have one for sale, is listed on Audiogon check it out and check the reviews. This Amp is like new and the price is good. This one will make you happy.

Sim Audio sound great with these speakers.

Try the Rotel amps or intergrated amps , Very nice and reasonable price

Vandersteen speakers will work with a lot of amps. I've cut back the power from 200 watts per speaker to 50. My room and my hearing don't demand more. I will say all of my amps have good power supplies that double power into 4 ohms and sound good and you're set.

Wow, really great responses here!
Ayre, Sim Audio - would LOVE to try these, but they are far above where I would like to be for cost, which is below $1k.
Atmasphere - fair point, the kids aren't babies anymore, so it's not as big of a concern as it was a few years ago.  There doesn't seem to be much available used below $1k.  Any thoughts on particular models that might be interesting to look at?
Bombaywalla - I can't say I'm a fan of MOSFET or BJT output stages in particular.  My theory is that it's more about the execution and working around the peculiarities of the technology rather than one being inherently better than the other.  The 2CE has an interesting impedance plot, averages maybe 6 ohms with dips to 4 ohms at 40Hz, and 3 ohms at 5kHz.  So not an overly taxing load (not worried about amp stability at all), but could result in frequency response deviations if an amp can't deliver the current it should at 3 or 4 ohms.
digepix - I'm in the same camp with power.  I have 300wpc now, and while that is entertaining to "wow" friends briefly, the majority of my listening is at very moderate levels.  I should put an oscilloscope on the speaker leads and see how low it is really.

Atmasphere - fair point, the kids aren't babies anymore, so it's not as big of a concern as it was a few years ago. There doesn't seem to be much available used below $1k. Any thoughts on particular models that might be interesting to look at?

A lot depends on the room size and your listening habits as to how much power you will need. In many installations 60 watts is plenty of power and there are a lot of great amps with 60 watts. The impedance of the speaker does not seem to be a problem.

You started with the Pass Aleph 5 so guessing you know of one that's in your price point. I'd go for the Pass; it's a great amp and it will not be outclassed by your Vandy's which are nice speakers. I know both products having owned the 2CE's and listened to the Aleph 3 and 5 at the dealer when they were current pieces. The Aleph 5 will run no hotter than a tube amp but it is hot to the touch; just don't touch it when it's running. If you're in a real, real small room in the desert it might cook you out but I doubt it. The Aleph 5 will drive your speakers no problem. If you don't like the Aleph 5 you will not have a problem reselling it I as they don't last long on the market.

The nice thing is the Vandersteen 2Ce is a good speaker but it's reasonably priced. I've used Rotel, Krell KST 100 and a YBA 3 DT to drive mine. If you like the sound of the Pass I would go with that. My Krell runs to half power (50 watts) in class A and that's plenty for the Vandersteens with a little extra in class B. You can spend a lot more on amps but were is the diminishing point, I think I've reached it.

Older Classe' and Musical Fidelity are sonic matches as well.

Pulled the trigger on a Pass Labs Aleph 5 that was for sale locally at an attractive price.  The build quality is phenomenal - a real piece of industrial art.  Sound quality is certainly there - nice detail in the high end, clean midrange and powerful bass.  60 watts is certainly sufficient in my room with these speakers.  Very pleased.

Now wondering what an external DAC will do for this setup... seems like a good topic for another thread!

a good DAC will do a lot, and need not be expensive

there are a few very good older threads, discussing the poor quality DAC in the Sonos as well as well as jitter issues

I just got a Schiit Bifrost Multibit for my PC, and am very impressed with it.-Especially, the price-about $600 bucks. They also have a return period.
I also use the McCormack DAC-1 and recommend it highly. 

I'm thinking Parasound ZDAC, DAC Magic, Benchmark DAC1, or the Bifrost.  Hadn't considered the Multibit, but it does look interesting.  Obviously just going to have to try something and see how it goes.

Congratulations on the amplifier purchase!  Hope it brings a lot of long term satisfaction.

As it seemed you felt open to consider tube amplification, the best amplifier I have listened to with Vandersteen 2 speakers was the Music Reference RM9. At the time, this amplifier - loudspeaker combination retailed for $4500, and sounded simply magical. Pricing has risen slightly, yet the sound will still beguile.

Your concerns for the children would also be taken care of by the tube cage.

I am going against the grain here, but doing so with a little experience with these companies. First off I am a Parasound fan. The A21 (which I own) and the A23 are engineered by John Curl. He is a very good engineer. I have also owned the DNA125 model of McCormack. A great amp but it developed a slight hum. Nevertheless it was old so I thought it was very good before it developed the hum. I have had three Odyssey pieces and was disappointed with all of them. They all developed hum and spurious noise even when one piece was new. I cannot recommend this company.

So the two amps I had from Parasound were the best for my 2CE Sig IIs. I had a 5 channel amp HCA855 which was very powerful for a HT amp and the A21 which has just been outstanding.