Quality of recording while evaluating speakers

It is a good question that been ask alot. In my prospective to this is that you should evaluate with music you like and familiar with. The reason why music with limited instruments is because space between frequencies. What I mean by this is that like vocals and guitar in a recording, there is that much space so it is easier for the engineer to mix which does not require ant processing.  In the other hand, music with alot of input is a little more complex to mix and may require processing and EQing to sound right. Rock is good example of this since alot of instruments like guitars and vocals have a very strong midrange frequency band. It is the way it is and that is ok. I have to admit that I don't like harsh sounding but when I am in the mood, does it matter? Just enjoy the music 

Maybe to clarify the point a little, it's like when you're listening to music and something doesn't seem right and you wonder if it's the speaker or the music quality.  Another recording it sounds great. Life is like that.  If only God worked on that final seventh day think of all the problems this would have solved.

Use as wide a range of recordings as possible. Some "audiophile approved" records do not reflect what one might ordinarily listen to. I have a thing for ’70s era post bop- not exactly a high point in vinyl quality. But nonetheless revealing since many of those recordings were done without a lot of production. They will allow you to hear acoustic instruments in what are typically small groups.

Of course, if your diet consistent of highly produced rock, pop, or the like, you should use those too, since that is what you will be listening to, presumably.

Punchline for me: choose a wide range of different recordings. You want to hear strengths and weaknesses of what you are evaluating. The biggest hurdle is often translating that into what you’ll hear in your system at home. That’s why I like to audition gear in my system. I can pretty quickly get a handle on what it is doing, good or bad.

J Gordon Holt (founder of Stereophile) recommended his readers do as he did: make your own recordings. I did so, recording my son’s speaking voice (a brutal test of loudspeaker coloration), my drumset, and my band playing live in a club. A pair of small capsule omni mics plugged directly into a Revox A77 Mk.3. That recording captured an inebriated patron bellowing out "How’s your boogaloo? Git it on RIGHT now!" Priceless.

Gordon also proclaimed this timeless truth about recordings: "Often the better the performance, the worse the sound quality. And visa-versa." An unfortunate truth. Lots of my favorite music suffers from mediocre or worse sound quality. I’d much rather listen to, say, Hank Williams, Little Richard, Jerry Lee Lewis, Little Walter, and Big Joe Turner than I would to, for instance, Steely Dan and Joni Mitchell. But that’s just me.

Fortunately, lots of Baroque-era Classical and Bluegrass recordings feature excellent sound quality. My number one priority in reproduced sound quality is how real singing voices sound. Get that right, and you're at least halfway there.