I will add to the statement I made - If BoredSys had made a statement that it would be almost impossible to tell the difference between 2 different amps I would whole heartedly agree with him.... But there can be huge sound changes made with Pre-Amp and the different implementation DACs and build strategy.
The differences will be extremely slight between different amps...
I agree to some extent on that, but I believe there are large differences (large is a relative term), especially as you move from cheap receivers to better recs. to separates.
I have a middle of the road Yamaha HTR-5650, about 5 yrs old, and my RX-V995, 10 years old. The power output is similar between the 2, 80 vs 100 wpc, but the 995 sounds much better. I believe it is due to design, from Yamaha's web site about the 995:
"DISCRETE POWER TRANSISTORS
Discrete power transistors rather than IC chips are used in the amplifier section to provide the cleanest sound possible. The amp delivers 100 watts each to the five channels."
Their web site says nothing about that feature for the 5650, that may or may not be the reason for the better sound, but it definitely is better. When I first hooked up my BIAMP Eminence 300 amp to the pre-outs of the 995 to run my old BP-10s (sold), there was a very noticeable improvement in sound quality, although both are rated 100wpc. I also tested the difference with my Athena S2's, again, noticeably better sound.
Out of my amps, they do sound very similar, although the Adcom sounds noticeably less open and detailed. That is why I use it to run my surrounds.
But this isn't about amps, I am happy with what I have and/or plan on getting in that arena (looking at an Acurus A125x5 to run center and 4 surrounds-Demote the BIAMP and Adcom to lesser systems or sell them). I will have tested the DC-2 by next weekend and report on it then.