And don’t have any equipment on high racks between speakers. Not having anything other than room treatments between speakers is perhaps the most important thing in getting 3d imaging. You can have equipment low to ground, anything higher than 20" or so starts affecting my sound stage.
My speakers are on my desk and between them there is a dac and amplifier and the computer screen.... 😁😁😁😁
The 3-D imaging dont comes from the interaction between the 2 speakers, but from the interaction between the speakers and the content and form of the room and his acoustical settings...
I own an under 500 bucks system which is able to give me a soundstage filling the room... A 3-d imaging which is spectacular in my 2 listening positions on the same level : near listening and regular listening...
The opposite impression about the necessity of an empty void between speakers comes from the fact that most people ignore the fact that what we are listening to is a complex set of waves crossing the average small room 15 times a fraction of second, then we never listen to an abstract addition of sound waves coming directly from the 2 speakers for sure, we listen to our entire system speakers/room with a complex grid pf pressure zones emerging and distributed in all the room in all directions......
For sure it is better or easier to have an empty space between the speakers but we can compensate by acoustic controls...
Another myth is the claim that near listening eliminate the room problem.... It is completely false in small room... We listen to ALL the room even at 3 feet of the speakers.... The ears/brain "compute" all the room pressuring zones content to create sound...
My acoustical material treatment and active acoustical controls modification in my room transformed completely the imaging, timbre perception and other acoustic qualities EVEN at my 3 feet listening from the speakers and on the same level of improvement than at my regular 8 feet location in my 13 feet "bad" small square room......