Is soundstage DEPTH a myth?

I had a recording studio for 10 years and I can assure you that to a recording engineer, soundstage depth is "a thing." Depending on the band and the source material, I worked very hard to create an illusion of soundstage depth using several well known techniques.

Creating the illusion that some instruments and voices are behind others involves using carefully structured reverb and delay on each track besides volume differences and EQ (not to mention how the instrument was actually recorded). The engineer can vary the timing of a delayed reverb, the length of the tail, the frequency response of the reverb, and other cues to make it sound like some instruments are further back than others. Most engineers would be very disappointed to hear someone say that there was no soundstage depth to their recordings.

If you read the recording notes of many modern classical recordings you will see that the engineer uses several microphones placed near the orchestra and various places in the hall. The mixing engineer then can manipulate these individual tracks to create the illusion that you are sitting in that hall. I've got some classical records that have caused people unfamiliar with audiophile sound to sit there gaping in awe. One friend exclaimed loudly, "How does it do that!!!?"

In contrast, some genres like hardcore want zero depth. They want the sound to be in your face, in a flat plane between the speakers. Obviously, this demands a different set of recording and mixing techniques. I can tell you from experience, it's not easy to get that sound.

I'll give you an old example to test. Santana's first album has a very good soundstage with the illusion of depth. If you hear a flat soundstage where all the instruments sound like they are in the same plane my advice is to work on your system. If you haven't been to an audio show I would suggest that you start there. You will definitely hear some systems and recordings that are downright spooky in how they create the illusion of depth.

Here is a relatively quick test to see if you can hear this phenomenon. Move your speakers out into the room and move your listening seat if needed so that you are listening in a very nearfield setup. Put the speakers about 3 or 5 feet in front of you (experiment) and sit exactly between them. You should get an effect approaching that of wearing headphones. The sound should be "holographic." Hopefully you should hear the illusion of depth on good quality recordings. Once you hear this you will "get it." Too often audiophiles constrain themselves with speaker setup that prevents achieving a deep soundstage. For an afternoon, forget WAF or any other constraint and play with your speaker and listening location. Maybe you can't leave everything in the optimal listening position but you you will know what you are shooting for and you can try to get it as close as possible.

For me the illusion of depth is one of the most thrilling aspects of this hobby. Sometimes when I'm listening to a favorite well recorded title I just smile and shake my head. I've heard this thousands of times and it still blows me away.

@hypoman 

Your comments are among the most relevant to the issue.  Many pop/rock recordings, and other studio recordings, don't have genuine depth.  Well-recorded orchestral recordings are perhaps the best for hearing depth, partly because there is more physical depth to an orchestra than to smaller groups.

I suppose you also have to have some level of quality in your electronics--there needs to be enough transparency to hear the depth clearly, and mid-fi electronics may lack that.

@8th-note You are very welcome to give us some more (non-classical or electronic) examples of (maybe your) recordings with great depht. Where the depht really adds to the experience of the recording.

It is no myth, and you don’t need to spend a ton of money.

But you do need to get things right.

The speaker spacing, both to each other as well as the back and side walls, is very important. You also want "time alignment" between the drivers.  And you want symmetry in the room. Soundstage/imaging/depth are all dependant on constructive as well as destructive interference and phasing and for these to occur properly, both speakers essentially need to be the same and "see" similar environments so they are the same in the seating area.

And..., if you want to feel "encompassed," you’ve got to bring the volume up to realistic listening levels!

I know it sounds cliche, but I’ve spent years putting together and perfecting a pair of speakers that image like no others I’ve heard. And I have JBL L200/300, JBL L112s, Altec, Big Red Supers (triamped), and Chartwell LS3/5As, and have heard Magico and Focal at demos, as well as lots of other varieties at listening parties.

If you get down to the Orange County, CA area, you are welcome to come by and hear what it is all about. Meanwhile, I leave you with this YouTube video. This is just the two inner speakers playing with no sub attached, no eq, and no room correction, either physical or electronic. The room is large (27’ x 16.5’ x 7-1/2->15’ ceiling, and open to the entrance hall and dining room.

This is an SACD played on an Oppo95 ($300 used) through a Yamaha RX-Z9 RECEIVER ($4,050 new at 10% off in 2002) in "Pure Direct" mode. The speakers use a JBL 18" 2241H, JBL 2251J, and ESS Great Heil that I’ve modified ($1,500 total investment with used drivers but new crossover components from ebay).

This shows the spectrum in the seating area without the 18" connected to alleviate the "noise" associated with floor and room bounce. I know it look a bit "bright" but that is a personal preference and I think it makes music more lively and brings out the microdetail. As shown, the crossovers are all the way up and there is even a "flat switch" that removes the upward tilt, engaged for overly bright or noisy cuts.

All caps are Audyn Q4s, all resistors are Dale 1%, all inductors are heavy-gauge air core.

So what do they sound like? Well if you believe in YouTube (many don’t) put on some really good headphones and take a listen. And while you’ll hear a nice smooth response, and lots of detail, you loose the imaging, but are welcome to come by for a demo any time. This was recorded on a Nikon D750 DSLR.

https://youtu.be/oLgQCHmXSUU

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.