Speakers that can reveal orchestral instruments' positions

My answer to the original question is YES.  However the degree to which one can hear specific locations within a soundstage is dependent on the quality and synergy of equipment used.

I hear width, depth and height from my system, in my room.

My reference is a Jazz Quartet.   Can I close my eyes and point to the location of each musician ?    Does the soundstage allow me to see the drummer moving brushes along a cymbal ?  Is transient response good enough to hear the initial strike of a cymbal or drum head, then the sound of the material struck, then the decay of the note ?  Do I hear each drum head in distinct space ?   Does the image project brass notes as distinct notes, or blended together without much distinction ?   Does a vocalist move their head around the microphone ?

I have experienced pinpoint imaging, and answered YES to the above questions using the following speakers:

Triangle Titus 202
Rogers 15ohm LS3/5a
KEF LS50

The KEF are a recent acquisition and I am still tweaking location to achieve best performance.  Currently, they are about 6 ft apart, about 3ft from side walls and about 4ft from the back wall, and I sit about 6.5 ft way from the center line.  The cabinets are toed in slightly.  Imaging is superb (pinpoint again), along with frequency extension.  But I hear some upper bass/low midrange emphasis that affects vocals.  I understand that careful positioning can largely remove this issue.

The ability to hear pinpoint imaging was improved by changing to a Triode TRV-P845SE as my main amplifier.  I have also used recently restored MAC 225 and 240 to good effect.  I heard the Triode amp at several audio shows, and at each show the room it was in was among the best I heard.  I waited patiently, and finally acquired one at an attractive price.

Preamps have a significant impact on the image one hears.  I thought I was doing well using a Conrad Johnson PV5.  Then I acquired an Audible Illusions M3 preamp, which was a significant improvement.   A few years later, I upgraded to an Audio Research SP10-MKII.  WOW !  Not only pinpoint imaging across the space in front of me, but I could hear depth and height !   I could hear fingers moving up and down the neck of a standing bass.   I could hear the relative locations of a trumpet bell, and the mouth of a tenor saxophone.  Each occupied distinct space that could be identified as they played in unison.   More recently, I picked up an Audible Illusions M3B (current model). This pre retains the virtues of the ARC SP10, but has a silent background and better transient response. 

Equipment:   Linn LP12 ITTOK LVII / Denon 103D SS Ruby rebuild / Cinemag 3440 SUT   -or-  Technics SP25  AT1503 MKIII arm / Ortophon CG25DI MKIII MONO cartridge

geoffkait:  "Actually, speakers image height real well unless you have system issues OR you system is not optimized"

No, that is just not the case. I know many want to believe this, but it is physically impossible. It is impossible to encode this information on 2 channels of audio. If the different frequency drivers you are using are spaced far out on your speakers, or have significantly different vertical dispersion, then an artificial illusion of height that bears no resemblance to the original performance, or even what the engineer thinks they are recording is possible, but that will come with it all kinds of other issues. Being an artificial illusion, it is not "imaged", as that would imply a level of accuracy.

iopscrl:  "Not only pinpoint imaging across the space in front of me, but I could hear depth and height !  I could hear fingers moving up and down the neck of a standing bass.  I could hear the relative locations of a trumpet bell, and the mouth of a tenor saxophone. Each occupied distinct space that could be identified as they played in unison. "

That perception of fingers moving up and down the neck of the bass would be your brain filling in information that does not exist. Your brain knows enough about how that bass is played to translate audio clues into a perception of what is happening. Our brains can do a lot to fill in information that we don't have based on prior knowledge. It does work better when we get rid of the other chafe.

I would agree that the most important factor is the recording quality. From my collection, The Power of the Orchestra, Moussorgsky, A night ..., Pictures ... (LP, reissue) images much better than most. Definitely I can hear the depth. The problem is, not many recordings are that good.

My room is not treated. I might try to improve the room treatment.

@ihcho As I posted above, YES, your ROOM is the most important element of any sound system.

Of course the quality of the recording is important.  Direct-to-Disc recordings from Sheffield Labs and others are about as good as it gets.  Decca as well, and some above mention many others.

I stand by my suggestion: adjust your room, get some good recordings, and then try Magneplanars last.

Cheers!