I think the best way to judge the quality of a stereo system is a comparison with live music, piano, voices )solo and grouped), in various environments. I've never heard an audio system that truly sounds like a Steinway grand, but some come very close. Using a known excellent system as your standard is not without some problems, because it is in a different room and probably at a slightly different volume. Don't just focus on transients or the bottom and top of the spectrum. You can usually tell is a system is good in the first minute of hearing it. After that your brain begins to accommodate it. Real music (and the memory can recall it) is the better standard. This is an easy test: the length of time you can listen to your system before you have audio fatigue. If you can listen for 5 hours and not feel unsettled, you have a well-behaved system.
