Is soundstage DEPTH a myth?

Our ears have no direct depth perception mechanism like our stereoscopic eyes do. Our brain can simply measure the convergence angle of our eyes for things up close. Once the convergence angle gets close enough to zero everything is just far away. That’s why the moon looks like it’s the same size and distance as the sun. Or maybe you can see that the sun is over 200 times the diameter of the moon just by looking. I can’t tell.

But there are definitely indirect ways for our ears to perceive depth, and the most obvious methods are reverberance and tone. There’s also another potential way of perceiving depth with sound and that is lateral shift as you move slightly. As with visual perception, things close will seem to move quickly relative to your motion, while things that are far away will seem to follow you along. A strange effect of the phantom center image when using just two speakers is that sounds that are panned hard to each speaker will tend to stay put, so as you move your head left or right you will get proportionally closer or further to the apparent sound from each speaker. On the other hand, center panned images  tend to follow your movement. If you move left, the center panned vocalist seems to follow you in that direction. This could conceivably create a sense of depth for some people, and may explain why they don’t like a center speaker for music. The center speaker will pin the vocalist to one specific location and that could make them seem closer. That’s a complaint I’ve heard and taken interest in because I am an oddball who absolutely LOVES a center speaker for 2 channel playback of music, but I try to commiserate with those who disagree with me. I really don’t care much about soundstage depth but I continue to perceive it on 2 channel recordings whether I’m just using 2 speakers or deriving a center channel.

@toddalin  

 How did you get stereo in the recording? The mic. in the picture looks mono. It’s interesting to hear the original track over headphones and then compare it to you recording, which sounds more reverberant and brighter.

The Behringer mic used to display the spectrum is mono. You cannot "analyze" mono pink noise through both speakers simultaneously because of constructive and destructive interference in the room. I've shown only the left speaker, but the right is similar.  The audio recording was made with a Nikon D750 DSLR camera.

Yes the recording is more reverbrant because it picks up the untreated, big, room acoustics. The brightness is my preference (but also the room) and could be turned down at the L-pads or flattened to a more conventional curve with the switch on the crossover.

Thanks for clarifying the use of the Nikon camera’s microphone. You had mentioned that but I didn’t make the connection to it also being the audio source. Is it the camera’s built-in mic. or a separate mic. you attached? I can hear the stereo separation.

I own that same Behringer DEQ2496 and it's calibrated microphone. It's been a useful tool over the last 15 years or so that I've owned it. Yes, you can't calibrate the tweeters at the same time unless you can somehow get the distance to each tweeter exact within about 1/8". That should get you up to about 10,000 Hz. Of course our ears are separated on our head so our ears really don't like two tweeters playing into both of them at the same time either. At least my ears don't care for it. 

When I finally bought a nice Dac and streamer for my smaller system for the 1st time I heard the imaging/Soundstage. I thought it was just a myth too as this was my 4th system and my cheapest one. Streamer to Dac to SS integrated to bookshelves. So when I heard it I began to question why my large living room sytem with expensive gear wasn’t similar if not better. Expensive tower speakers and hand built highly detailed low distortion(likeSS low) tube amp with a pretty high end turntable. So I began trouble shooting w speaker positioning, changing my interconnect xlr and rca connections. I finally nailed it when I changed my modern tubes to NOS Ken Rads. So now massive, massive soundstage far beyond the side walls of my living room and 3d imaging. So yeah two diff systems two different solutions. Or maybe neither system was ever set up properly or some aspects of equipment wasnt allowing me to get everything out of my system until I addressed them. Whatever the reason I would not stop tweeking things until you've arrived. You’ll know it immediately when it happens even if you’ve never heard it before(as in my case). Best of luck enjoy your journey.