I had the thought that one way to distinguish an audiophile/high-end audio system from a mid-fi one is that when you're in another room and hear the audiophile system playing a good recording of an acoustic instrument or ensemble, it sounds like they could actually be there in the other room. I don't hear that with lesser systems.
I wasn't sure this was worth starting a thread about, but it's more germane than most of the other comments here, even if some are humorous.