Thanks for the amusing post! First of all it depends on the resolution of the system and the acuity of your ears!
First all Vandersteen loudspeakers have recessed treble and are not as highly resolving as other high performance loudspeakers, I am not saying they are bad speakers, however, they are voiced on the soft and laid back side.
In my shop I can do similar comparisons and some of the differences are monumental:
I have compared many dacs from Bryston, Benchmark, Cary, M2 Tech, Hegel, Esoteric, AMR, Meitner, Naim, Rega,Cambridge Audio, and they all sound quite different! They all differ in terms of resolution, sound stage width and depth, bass definition and impact, and warmth or lack of warmth in the midrange.
What I will agree with you is that many of the dac's priced in the $1,000.00 or so range do sound similar, however, that is not an earth shattering concept, many integrated amplifiers in the same price range offer similar performance and differ in the above criteria as well.
Dudes buy a box of Q Tips, and pay me a visit I can demonstrate to you that your findings are only accurate in your limited set of circumstances: your system setup and your ears, extrapolating your particular biases and expectations to the rest of an industry is fallacious.
Do you think the market would bear so many different dacs at so many different price points if they all sounded the same? Do you also think that everyone else here is delusional when they post that they switched from brand x dac to brand y and heard a huge improvement?
Hey what do I know I have been doing this as a profession for 25 years.
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