If you are going for accurate, open sound at un-amplified volume with orchestral range, I second the recommendation for Sound Lab's.
Eminent Technology will get you most of the way there for a lot less money.
It's hard to beat planars for quickness and immediacy.
There are plenty of accurate, ruler flat speakers today that allow you to pull eveything out of the source.
Unfortunately, there's also lots of poorly mixed sources, too.
I went through several high quality, accurate monitor style speakers until I figured out it was the source material that was the weak link.
I switched to a coherent style speaker (Ohm 2000's) that is 'voiced' to be more tolerent of the source and yet still pleasing.
It satifies my tastes but took some years to get there.
If I had the space (and cash), I'd go Sound Lab...ha. They are stunningly good.