Soundstage and image height, does it exist?

To quote Bobby Owsinksi from The Mastering Engineer's Handbook:

The LEDR test is a substitute for about $30,000 to $40,000 worth of test equipment.

Stereophile also has an article about it, written in 1989 (!) by Bob Katz:

"My system has great imaging!" "I can hear sound coming from beyond my speakers." "The depth image in my system goes back at least 20 feet." Yes, we audiophiles are proud of our imaging (footnote 1), and we've worked hard to get it. My back is still aching from the last time I tweaked my speakers until the image was just right. Wouldn't it be nice if we had a test to set up and check a stereo system for correct imaging? Yes, Virginia, there is an imaging test—your LEDR is here (footnote 2). LEDR, which stands for "Listening Environment Diagnostic Recording," is available on a test CD from Prosonus, the Studio Reference Disc (footnote 3). The CD is rather expensive (about $50), but there is no other official test for imaging. [Since this article was published, an LEDR track was included on the first Chesky Records Jazz Sampler & Audiophile Test CD (JD37).—Ed.]

Luckily it's 2022 and we don't have to buy expensive CDs anymore, as there is an online version of this test here: http://www.audiocheck.net/audiotests_ledr.php

The Stereophile article has a rather lengthy explanation about what you should hear - the short version again quoted from the Mastering Engineer's Handbook is:

If the sound for the up image doesn’t go straight up from your loudspeaker, six feet in the air as you sit there in your position, then you’ve got a problem with your crossover or with reflections above the loudspeaker.

If the sound doesn’t travel from left to right evenly and smoothly with the left-to-right test, then you’ve got problems with objects between your loudspeakers.

And the same with the beyond signal, which is supposed to go from about one foot to the left of the left speaker, gradually over to one foot to the right of the right speaker, which detects reflections from the side wall.

I apologise as I have not had time to read all the responses to your question about image height but this article was published in the Absolute Sound and was part of a series of articles about being able to determine the best digital audio music files - wav/flac etc - and computer file servers - windows/Mac. The writers of the artiicles used image height as a 'measurement' of sound quality - the higher the image the higher the quality. I use this method - not in a measured way - but listening for the height which equates to me as better/best sound quality. It usually correlates to high frequency content and higher or highest resolution in the music being played. The article - one of them is here - if you scroll down until you find image height the context can be read. Hope it helps?

 

= High Fidelity = Full range. Box/xover speakers aint going to out perform a  Full range, = Sensitivity issues. under 90 db vs over 92db, High sens always wins out in a  shootout every single shootout. My tech here in new orleans continues his mantra,, **Well you do have a  xover in your speaker, ..** I tell him over and over,, sure its a  single cap, acting  as  a filter on the 2 tweeters per channel. Each T has a  8.2 Mundorf SESGO cap,. Which blocks fq's at the 4kish range.  I am speaking of xovers on both tweeters and woofers ina  typical box design. My Seas Thors had 1 coil + 2 resistors + 4 caps per tweeter then the woofer had like 1 res + 1 coil + 1 massive cap. 

A Full Range has no xovers. 

Which allows the purity of the music to sing natural. 

A woofer never will out shoot a  Full Range, = Higher end FR, not lower end. 

Some FR are garbage. A few are true high end speakers, which IMHO will never be surpassed in high fidelity. 

I have a  8 inch FR + a  6 inch FR + dual T's per channel. Open baffel. FR sound like garbage ina  closed/ported box.

But of course most of you here have not heard a  FR in action, so you would not know what I am tlking about. 

For me, FR is top dawgs. 2nd to none. 

Out shoots all panels/Stats/horns. 

height which equates to me as better/best sound quality. It usually correlates to high frequency content and higher or highest resolution in the music being played ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~ Exactly, the higher sens drivers always presents a cleaner more accurate = more detailed musical image vs low sens drivers. Ideally no driver under 91db and not over 95db are the ideal sens range for any driver

That speculation cannot be disproved, but with my line source speakers there is no height with the sound stage. The stage expands laterally from both speakers due to phase interactions.  This also might explain the sound source coming from behind the listener, in a room where all four walls are completely insulated. 

There is a lot of neurological processing regarding phase reception given the fact that the 1D axis of two ears yields 3D hearing so I would look more to that as an explanation.