Soundstage and image height, does it exist?


On another site, there is a discussion on soundstage, and there are a few people clamming, that, since there is no vertical information encoded on stereo recordings, that soundstage height does not actually exist. It is a product of our minds filling in missing information. 

Are they correct?

Please explain your position, with as much technical details as you feel needed.

 

128x128simonmoon

My understanding of human sound perception of height is that it occurs mostly in the pinnae, causing the tonal relations and phase relations to change at the eardrum. There are no timing or level differences that can give us height information so a two channel playback system doesn’t inherently have anything to work with. But we may perceive a ceiling echo in a concert hall recording as coming from above from other unconscious means of deduction. You could say it’s our imagination but it would be informed imagination. If a recording is made using a dummy head then tonal relations associated with height do get encoded onto a 2 channel stereo recording. All directions are possible, but it usually doesn’t work super well because 1. Our pinnae are not all the same, and 2. The sound goes through the pinnae transformation twice - once at the dummy head microphone and again when the sound from the speakers hits your pinnae. My experience with listening to dummy head recordings through speakers is that the height effect can make it through all these issues with powerful effect sometimes. I have a recording of airplanes flying over that creates a very powerful directly overhead effect on every speaker I’ve tried so far.

Any system that has a tonal response that mimics your tonal response for height can cause a height effect for you. Ceiling reflections can also create a height effect. And of course speakers up high can create that effect. My speakers tweeters are higher than my seated position so I have an elevated sound stage.

Image height is a function of the reproduction chain, loudspeakers in particular. If it was simply a matter of saying that there is no vertical information encoded in stereo recordings then the resultant sound stage would be non existent in the vertical plane.

 

This first time I heard height reproduced through a hi-fi system was when I played Boult's recording of Holst's The Planets (EMI ASD 2301) on a Thorens TD-125 Mk.2/SME 3009/Decca Blue pickup turntable, feeding pair of Magneplanar Tympani T-I's bi-amped with ARC tube amps. Way, way at the rear of the hall (which itself could be heard) I could "see" the percussion instruments (particularly the triangle), raised on a podium above the instruments in front of them. I didn't yet know symphony orchestras were so situated, and had no expectation to hear that sound. Yet I did. 

@roxy54 --

With speakers I guess it’s all about the way the drivers disperse the sound.

+1

I like that the actual, total radiated field of sound extends somewhat beyond the listening height (with a line source ideally terminated at both the floor and ceiling) dictated by ear level above the ground. My own speakers are just above 6 ft. tall, but the acoustic center at the LP is situated between the upper edge of the bass bin and the lower edge of the horn above (i.e.: at 100-105 cm’s). This way there’s a sensation of what’s presented to the ears as being less restricted and more immersive (or fuller), and so there’s a larger "canvas" for the sound to emit itself from. Physical properties of sound that to my ears more closely emulates the signature trait of an acoustic live symphony orchestra concert, or even a live amplified one.

Whenever imaging or soundstage are mentioned, I like to remind people about these resources: The following provide tests, with which one may determine whether their system actually images, or reproduces a soundstage, as recorded. ie: On the Chesky sampler/test CD; David explains in detail, his position on the stage and distance from the mics, as he strikes a tambourine(Depth Test). The LEDR test tells what to expect, if your system performs well, before each segment. The Chesky CD contains a number of tests, in addition to the LEDR. (https://www.audiocheck.net/audiotests_ledr.php) and (https://www.amazon.com/Chesky-Records-Sampler-Audiophile-Compact/dp/B000003GF3) The shape of your ears’ pinnae is also a variable, regarding your ability to perceive images/locate sounds. A Stereophile article, that explains the LEDR test: http://www.stereophile.com/features/772/