3D imaging

What makes speakers produce a 3D image is being symmetrically equidistant and pointed towards the listener. Period.

All the other stuff contributes, of course. But you asked specifically about speakers. 

But hey, don't take my word for it. Prove it to yourself. Point one speaker off to one side instead of at you. Move one a foot closer or further away. Notice nothing else changed- same recording, same room, same components.

Speakers are like real estate: location, location, location.

If you want to do some research, look into Head Related Transfer Functions.

For most speakers, having good room acoustics is key.

Thanks for the input millercarbon. I rotate 3 sets of speakers in my system,(Hornshoppe Great Horned Heils,Nola Boxer 2's,and Graham Chartwell LS3/5's). They all throw a great 3D image,so I guess I'm doing something right. I was just curious if the speaker design was responsible. 

 I've read posts on other forums where posters think that attaining 3D imaging is just chasing unicorns. Obviously they are doing something wrong. 
   
  As a side note,I've been at this hobby for a bit,and I'm no spring chicken. I just don't have a ton of technical knowledge. This is one reason I frequent this site. There are a large number of members here that DO have a vast knowledge of things audio. I find that exposing myself more to the technical aspect of this hobby will help me understand what I am hearing to a greater degree. 
    Again,thanks for your response,
           Ray