Speakers that can reveal orchestral instruments' positions

Eat some acid.....no problem

Magneplanars, of course, but your ROOM is more important than any speaker.  

Work with your dealer, assuming you have a REAL dealer, to ensure that your room is set for the best sound.  THEN try all the speakers you want. 

If you have good electronics, listen to the Maggies last.

Then pick whatever speakers YOU like best.  FYI, when Jim invented these speakers back in the 1970's, one of his main goals was to be able to do what you are asking, so...

Cheers!

TANNOY

Thanks for all replies.
Tvad, you are right. I don't get lucky most times to have a mid center seat in concerts. Newbee, you are right. I should just enjoy music, rather than thinking about instruments position.
Mozartfan, I like my Tyler, and I had pretty much enjoyed its sound. But I was still not quite satisfied with full orchestration classical music. Then, I bought Diva from my friend, and there was no comparison to Apogee Diva in terms of sound stage and true color of acoustic instruments and human vocals. I like my Harbeth too, and it does pretty good on acoustic instruments, jazz and vocals, but still it lacks much in sound stage and details of full orchestration music compared to Diva.
Well, it may not be a fair comparison because Diva is in a different league. 
Sadly I sold my Diva due to occasional buzz and it was just too big, and then I started missing Diva.
My main gears are Plinius SA102, M16, Esoteric UZ1 SACD player, Garrard 301 with Ortofon RMG 309 and SPU gold ref cartridge.