What do you consider the most musical speakers—$15000 & under

Those would be - Linkwitz Orions or LX521s or Legacy Aeris (if bought in the used market - below $15,000).

I just purchased the Vandersteen Quatro CT's (painted) over all the others I auditioned under 30k.  I found them to be the most accurate tonally, had the most detail as they dont' smear and are time and phase accurate.  They are the most musical since they offer the most detail.  The attack and decay are as good as it gets.  I think they are the sweet spot in Vandersteen's line.  The bass EQ let's you put them into the corner of the room up against the wall so the wife loves them too.  With the bass EQ, you can set them up to also max out the soundstage without getting suck out in the middle.  

These are just my suggestions.  The biggest thing you can do it go audition.  All speakers get good reviews, including many best of shows by Vandy's, Magicos, Legacy etc..., but that may not be your best of show.  That's a large chuck of change to spend and maybe a trip to a large city to go listen to a large cross section over a weekend.  Just a thought.

@shadorne the difference between a saxophone and a lawnmower? 
Vibrato. 

There is hi-fi and there is my-fi. I tend to believe that people want a system that sounds good to them.
I've been lucky enough to be in the studio with some great musicians and witnessed recordings first hand.
Unless we are in the studio how do we know what is accurate?
And if the system is truly accurate wouldn't some of these recordings sound like they were playing through Yamaha NS10s?
Everything in the studio gets processed. Snare drums have noise gates to prevent bleed over or the snares buzzing.
I can usually tell if the drummer is using a brass or wood snare or of he is using Paiste or Zildjian cymbals.
The guitarist is another problem, he is running through a pedal board, so how does one know if what we are hearing is accurate?
Usually the musicians don't even know what is accurate they just know if the performance sound right and too many takes kills the vibe.
For me,if I can hear those differences then all is good.