My stack of CDs will probably contain:
Cranberries - female vocals for high representation
Vince Guarardi - piano for clarity of simple tone
John Lee Hooker - low male voice and stage presentation
Willow/Robin Hood soundtrack - orchestral reproduction
Ray Charles - piano/vocal representation
Aerosmith - overall sound reproduction
Pink Floyd - overall sound reproduction
Any thoughts on the music? The system will probably be used for home theater and music listening, so I don't expect the smaller satellites to wow me.
I think vocal tracks are absolutely key, because there is no other "instrument" that you are more familiar with (unless you are an avid/professional musician, and even then). You hear, and have heard,
naturally produced voices everyday of your life. If not everyday, ok +99% of your life. We are so attuned to voices, it's how we learned, how we obey, how we command, how we order food, etc, etc, etc. Nutshell: I believe it is easier to be demanding/discerning of a speaker system with vocals, for the most of us, on most speakers, than any other instrument.
Piano, I agree it's about clarity, in a way. What I call it (or what musicians call it) is balance (or consistency of tone). However, if you aren't very familiar with complex polyphonic music for example, this may be harder to pick out. Besides other things. Anyways, a piano maintains its similar timbre very well throughout such a large range, and for me, it's not an easy test. Also, the inherently percussive/transient attack of a piano is something I think a lot of speakers cannot do easily. I have the suspicion that my HT speakers may have a tough time as well.
Lastly, if you love prog/rock, maybe you should just use that stuff. The reason being that's what you're going to listen to anyways. (I mean, do you really care that your speaker system can faithfully reproduce opera, even if it was deemed as more difficult?) Also, since that's what you love, that's what you're familiar with, which allows you to be more discerning. You're judging speakers on what you know, not discovering new music for the first time (as that may* prove distracting)?