Actually, most professionals (not just big box stores) assert that spending more on speakers will give you a more noticeable increase in sound quality. And the fact that "speakers can't add information that components upstream don't provide for it" is true. I'll concede that point. This is true in theory, but not necessarily in a real listening room. However, amps don't provide the signal, they only amplify it so that the current can drive the speakers. Therefore, you're really advocating spending more on CD players than on speakers, which I doubt many people will agree on, but which may fit your personal listening tastes more. The second point is that it is not usually the amp that is the LIMITING FACTOR to good sound. Many lower priced receivers (NAD, Denon, Onkyo) will reproduce a very similar digital signal when amplifying from a CD player. But it is how the speakers translate this signal into sound that makes people who appreciate good sound spend big bucks. That's why many professional reviewers say that spending more on speakers will yield an incrementally (again with marginal returns) larger increase in sound quality than spending more on cd players, amps, or processors as long as the components upstream are of at least decent quality and can drive your speakers without distorting or overheating.
Finally, I'm not saying that hi-fi audio is only for a deserved few. The post was about, and is still about, the notion of marginal returns, not about the establishment of an audio elite. If you can afford more and you can honestly hear sound quality differences, then more power to you. But unless you've been professional trained to listen for sonic differences, most consumers will reach a point where they honestly won't hear a substantial difference in sound quality, and especially not substantial enough to justify spending thousands more. At this point, at the point where you yourself can't hear any difference in sound quality or at least you can't justify to yourself spending thousands more to get an infinitesimally small increase in sound quality, that is where you should stop spending, purchase the product, and be happy with what you purchased without ANY regrets about not purchasing those $100,000 Wilson Audio speakers.
