"They are here" vs. "You are there"

Where I would differ with you would be on the subject of the listening room being much of a factor at all in picking up what you are calling "ambient cues" in the recording. The listening room is of course a big factor in the sound of a system as a whole, however I would disagree that it has much effect on this specific issue…

Learsfool – I have some thoughts that bear on your view that the listening room doesn't have much effect on creating the illusion that “you are there.”

As I mentioned in a previous post, my view is that ambient cues are the principal determinant of the illusion that “you are there.” The ambient cues of the recording are the most important. But the ambient cues of the listening room are, in my view, quite significant. Before I say exactly how, I should say…

A FEW WORDS ABOUT AMBIENT CUES:

So far, I have not defined ‘ambient cue.’ Here’s a stab at it:

Ambient cue: Audible information about the features of a physical space.

Ambient cues provide information about features of a physical space like: size, shape, materials, and object position. Ambient cues are contained in the relations between direct and indirect sound, including: relative amplitude, relative duration, relative phase, relative frequency content, relative harmonic content.

In an anechoic chamber, there is (virtually) no indirect sound, and hence (virtually) no ambient cues. In the real world, there are an abundance of ambient cues. So much so, that animals, and to a lesser extent humans, can use those ambient cues to echolocate. The point is that, in virtually all physical spaces, ambient cues are ubiquitous and highly informative. This brings me to…

THE IMPORTANCE OF AMBIENT CUES IN THE LISTENING ROOM:

Every listening room contains an abundance of ambient cues. The specific characteristics of those ambient cues are relevant to the audiophile, for the following reason:

During playback, the ambient cues of the recording space are COMBINED with the ambient cues of the listening space.

The combination of the ambient cues of the recording space with the ambient cues of the listening space creates, in effect, a NEW SET OF AMBIENT CUES. I will call this new set of ambient cues the “playback space.” In other words:

Recording space + Listening space = Playback space

The playback space is what the audiophile actually hears at the listening position. It is the combination of the ambient cues of the recording space and the ambient cues of the listening space.

When trying to create the illusion that “you are there,” an audiophile tries to create a playback space whose ambient cues are as close as possible to the ambient cues of the recording space. As I see it, there are two possible ways to go about this:

1. Construct a listening space whose ambient cues resemble the ambient cues of the recording space.

2. Construct a listening space that minimizes ambient cues.

The first approach is largely impractical, especially for those who listen to a wide array of music with vastly different recording spaces. However, I did read about one Rives audio customer who approached Rives with the request to build 4 different listening spaces, each optimized for one of four different types of music - symphonic, jazz, vocals, and rock. The far more practical approach is to minimize the ambient cues of the listening space. But this can be done only up to a point, since ambient cues in the listening space are essential for creating a realistic soundstage, another crucial factor in creating the illusion that “you are there.” This creates something of a dilemma for the audiophile:

To the extent that he constructs a listening space whose ambient cues resemble the ambient cues of a particular recording space, his listening room will be optimized for only one type of recording. To the extent that he constructs a listening space that minimizes ambient cues, he will diminish the realism of his soundstage.

The way out of this dilemma is some kind of balance between the two approaches. The exact nature of that balance probably varies from room to room, recording to recording, and listener to listener. But I suspect that there are some generalizations to be made. Otherwise companies like Rives wouldn't be in business.

Regardless of which approach is taken, the inescapable fact is that the ambient cues of the recording space will always be combined with the ambient cues of the listening space, to create the ambient cues the listener actually hears at the listening position (what I am calling the “playback space”). The only way to escape this fact is to listen through headphones or in an anechoic chamber, both of which are great for hearing the ambient cues of the recording, but lousy at creating the illusion that “you are there.”

Hi Newbee - I didn't take that comment personally, I just felt like responding to what is after all a very common comment made here on this site. You are by no means the only person who has made such a comment. I'm not offended by it, I just see it as a common misperception and was trying to explain it.

Bryon, your last post is fascinating. I think you are correct when you say that "ambient cues" in the recording will always combine somewhat with those in a listening room. However, after reading your post and thinking about it, I still think that the equipment, specifically the speakers, will have an even greater effect. The multchannel system example I gave before would create even more chaos in this area, no matter what the size of the room. And some speaker types will lessen the "ambient cues" of the listening room, such as horn speakers. This is actually another reason why many musicians prefer them when they hear them - the shape of the horn itself helps direct the sound more where you want it to go, minimizing some (of course not all) of the effects of the room in which they are placed. Therefore, one can hear more of the "ambient cues" on the recording as opposed to those of the room. This directness of horn speakers also tends to more closely approximate the "you are there" effect of live acoustic music, whether orchestral or jazz, especially in terms of physical impact.

Other speaker designers like to create a different sort of presentation, which many reviewers love to call more "laid back." This can sometimes be quite nice, Sonus Faber would be a good example of this type of sound. It is a beautiful sound, but it tends to de-emphasize the "you are there" effect - the soundstaging of these speaker types tend to obscure the "ambient cues" and they certainly do not have anything like the same physical impact, by design. Many audiophiles will say they much prefer this type of "laid-back" presentation, even for very large-scale music. There is of course nothing wrong with this, and it can be a very pretty sound, as I said, but for me it is most definitely not a sound that I would describe as life-like.

To go back to the term "coloration" for a moment, this actually illustrates why I personally do not like the way audiophiles use the term. For me, the more "laid-back" presentation of say a Sonus Faber speaker is much more of what I would describe as a "colored" sound as opposed to the more direct, lifelike presentation of say my Cornwalls (not that I am in any way promoting my Cornwalls as the best thing available, please understand, I am speaking of very general differences in speaker types here). I can hear more of the colors that the musicians on the recording are trying to create on my Cornwalls than I can on say a Sonus Faber Amati, as great as those speakers sound in their own way.

However, I fully realize that this is NOT the way most audiophiles use the term, and I would bet that most of you reading this are now scratching your heads, convinced that horns are some of the most "colored" speakers out there. But I digress, I certainly don't mean to turn this into a discussion of the merits of different speaker types.

As I said, I do agree with much of what you said - the only thing I would actually strongly disagree with was something you said at the end, that headphones are great for hearing the ambient cues - in fact I would say just the opposite. To me, listening on headphones, no matter how high their quality, sounds nothing like live music; nor does the presentation resemble a real space in any way, shape, or form. Frankly, I have always been very puzzled by those audiophiles who claim they are great for anything whatever, besides not disturbing anyone else with what you are listening to. They create no soundstage whatsoever, and imaging is also very poor, and of course stereo channel separation is greatly heightened, all of this resulting in a very artificial sound indeed. This of course assumes that the goal is to come as close as possible to the sound of live acoustic music in a good performance space. If you just want to rock out, than most of the above won't apply. I will say for them that they perhaps allow one to hear more of some kinds of detail, but definitely not the "low-level" detail we are speaking of here. I realize that you also said they are lousy at creating illusion that "you are there," but aren't the ambient cues a very important part of creating that illusion?

I think you are correct when you say that "ambient cues" in the recording will always combine somewhat with those in a listening room. However, after reading your post and thinking about it, I still think that the equipment, specifically the speakers, will have an even greater effect.

Learsfool – You may be right about this. Now that I am giving it more thought, it does seem that some speaker designs are considerably better than others at creating the illusion that “you are there.” So why don’t we just say that BOTH the listening room and the equipment are important factors in creating the illusion that “you are there,” though neither is as important as the recording. Or we could leave that last bit out, and just say that ALL THREE are important. That’s probably the most realistic view, in light of the fact that their relative importance is likely to vary from recording to recording, listening room to listening room, and equipment to equipment. That whole topic is a lot like the “Which is more important: Source or Speaker?” threads that pop up from time to time. Talk about an infinite staircase. So, moving on to speaker design…

...some speaker types will lessen the "ambient cues" of the listening room, such as horn speakers. This is actually another reason why many musicians prefer them when they hear them - the shape of the horn itself helps direct the sound more where you want it to go, minimizing some (of course not all) of the effects of the room in which they are placed. Therefore, one can hear more of the "ambient cues" on the recording as opposed to those of the room. This directness of horn speakers also tends to more closely approximate the "you are there" effect…

It is certainly true that highly directional speakers minimize the ambient cues of the room and maximize the ambient cues of the recording. But I am skeptical that highly directional speakers are inherently more likely to create the illusion that “you are there.” In order to explain my skepticism, I have to say a few things about sound DIRECTIONALITY…

A sound may be unidirectional, bidirectional, multidirectional, or omnidirectional, depending upon the number of sources, the nature of the acoustical environment, and the position of the listener. In reality, there is something like a continuum of sound directionality with unidirectional at one end and omnidirectional at the other.

In most interior spaces, ambient cues are typically OMNIDIRECTIONAL, i.e. they arrive from all directions. Likewise, in most recording spaces that are not acoustically inert, ambient cues are typically omnidirectional. That is NOT to say that ambient cues are EQUAL IN ALL DIRECTIONS. It is only to say that they ARRIVE FROM ALL DIRECTIONS (at the microphone). This fact bears directly on how to create the illusion that “you are there,” as I will now try to show...

As I mentioned in my previous post, creating the illusion that “you are there” is achieved by creating a playback space that is as similar as possible to the recording space. There are two approaches to this. The first approach is to construct a listening space whose ambient cues resemble the ambient cues of the recording space. The second approach is to construct a listening space whose ambient cues are minimal. Both approaches have liabilities, but it is the liabilities of the second approach that are relevant at the moment, for the following reason:

To the extent that you minimize the ambient cues of the listening space, the sound arriving at the listener will not be OMNIDIRECTIONAL. It will be BIDIRECTIONAL, assuming you are listening in stereo. Even if the recording has OMNIDIRECTIONAL ambient cues, what you will hear at the listening position is the BIDIRECTIONAL presentation of OMNIDIRECTIONAL ambient cues.

In other words, by minimizing the ambient cues of the listening room, the sound will arrive at the listening position primarily from TWO directions (the locations of the speakers). This means the ambient cues of the recording will, likewise, arrive primarily from TWO directions. But in the recording space, the ambient cues arrived from EVERY direction. That difference is the fundamental limitation in the approach of minimizing the ambient cues of the listening room when trying to create the illusion that "you are there." Hence...

(1) The BIDIRECTIONAL arrival of OMNIDIRECTIONAL ambient cues cannot create the illusion that "you are there."

In contrast...

(2) The OMNIDIRECTIONAL arrival of OMNIDIRECTIONAL ambient cues can create the illusion that “you are there.”

RE: (1). This is why headphones and anechoic chambers cannot create the illusion that “you are there.” Both headphones and anechoic chambers create a BIDIRECTIONAL presentation of ambient cues. But the ambient cues in an acoustically significant recording space did not arrive from only two directions. They arrived from every direction. This difference in directionality between an acoustically inert listening space and an acoustically significant recording space is an insuperable obstacle to creating the illusion that “you are there.”

RE: (2). This is why an acoustically reactive listening room is a critical element in creating the illusion that “you are there.” The acoustically reactive listening room creates an acoustical space in which the ambient cues of the recording can be presented omnidirectionally, JUST AS THEY WERE IN THE RECORDING SPACE. If, on the other hand, your listening room is acoustically inert, you reduce the possibility that the ambient cues from the recording can arrive from all directions. And if the ambient cues of the recording do not arrive from all directions, your playback space will be fundamentally different from the recording space, which destroys the illusion that "you are there."

Incidentally, this also explains negative reactions to recording studios that briefly appeared with a “live end” and “dead end.” In that design, one side of the listening room has an abundance of ambient cues, while the other side has virtually no ambient cues. That creates a more or less HEMISPHERICAL presentation of OMNIDIRECTIONAL ambient cues, which is not at all like the experience that “you are there.” Not surprisingly, this recording studio design was unpopular with recording engineers.

This brings me to why I am skeptical about your view that highly directional loudspeakers are inherently superior to, say, omnidirectional loudspeakers when trying to create the illusion that “you are there.” If you were to place highly directional speakers in an acoustically inert listening room, for example, you would create a highly BIDIRECTIONAL presentation. That means whatever ambient cues are in the recording will not arrive at the listening position from all directions, as they should. In fact, if you went far enough with this approach, you would approximate the sound of headphones and anechoic chambers, which is not at all the sound that “you are there,” as you point out. So if the listening room is acoustically inert, highly directional speakers are probably NOT the best choice.

Finally, I hope all this clears up the puzzlement you expressed when you said:

…the only thing I would actually strongly disagree with was something you said at the end, that headphones are great for hearing the ambient cues - in fact I would say just the opposite. To me, listening on headphones, no matter how high their quality, sounds nothing like live music; nor does the presentation resemble a real space in any way, shape, or form.

Headphones are great for hearing the ambient cues IN THE RECORDING, but terrible for hearing the ambient cues AS THEY SOUNDED IN THE RECORDING SPACE, because in the recording space, the ambient cues were omnidirectional, whereas in headphones, they are bidirectional. In other words, I agree with your comment that the sound of headphones does not “resemble a real space in any way, shape, or form.” But the reason is NOT because headphones fail to provide the ambient cues of the recording space. The reason is because headphones fail to present the CORRECT DIRECTIONALITY of the ambient cues of the recording space. With headphones, you are hearing the BIDIRECTIONAL presentation of OMNIDIRECTIONAL information. But in the recording space, you would hear an OMNIDIRECTIONAL presentation of OMNIDIRECTIONAL information. That is what the real world sounds like. And that is what we must make our playback space sound like, if we want to create the illusion that “we are there.”

Hi Bryon,

Your last post, while of course highly thoughtful, I would have to very respectfully say strikes me as being essentially a set of hypotheses, which are subject to challenge and skepticism in several ways:

1)Along the lines of some of our discussion earlier in this thread, there is little reason to expect, in general, that omnidirectional presentation in the listening room will augment or better present the omnidirectional information that was captured in the recording space, because of the vastly different delay times that are involved. Those timing differences will cause our hearing mechanisms to respond in completely different ways, per the Haas Effect and the Precedence Effect (for which Wikipedia links are provided in one of my earlier posts).

2)There would certainly seem to be ample empirical evidence, such as in the system descriptions posted here at Audiogon, that high quality directional speakers are not necessarily at a disadvantage, relative to speakers with broad or omnidirectional dispersion characteristics, in creating a reasonably good "you are there" illusion.

3)Omnidirectional presentation in the listening space presents in an omnidirectional manner not only the reflected sound that was captured in the recording space, but also the sound that was captured in the recording space via the direct path between instrument(s) and mics. The directly captured sound, of course, having a significantly earlier arrival time at the mics. Intuitively that would seem, at best, to invoke a significant tradeoff. Among other reasons for that is the fact that the frequency response curves of our ears vary considerably as a function of the direction of the sound source.

4)It seems to me that the major problem with headphones is not that the sound is presented bidirectionally. Per my item 2 above, speakers that present bidirectionally can, at least in many circumstances, present a reasonably good "you are there" illusion. The major problems with headphones are two-fold, as I see it:

(a)The sound we hear from them essentially bypasses the pinnae, thereby altering both frequency response and directional cues.

(b)Nearly all recordings are not mic'd to be compatible with headphone listening. A recording mic'd to be properly compatible with headphone listening needs to be recorded binaurally, which as you probably are aware means it is recorded via microphone capsules inserted in the ears of a dummy human head.

I have two or three binaural recordings, and they can be truly spectacular in their "you are there" realism, when listened to with headphones. Although the degree of that realism can be expected to vary somewhat from listener to listener, corresponding (I believe) to the anatomical differences that may exist between the heads and ears of each listener and the dummy head that was used.

FWIW, I'll add that on normal stereo recordings of classical music, if they are well recorded, minimally mic'd, and minimally processed, I can clearly hear ambient cues and hall effects on my Stax headphones. They do seem somewhat less prominent than when I listen via speakers, but I suspect that is due mainly to the relatively lean sonic character of these particular headphones.

5)

So why don’t we just say that BOTH the listening room and the equipment are important factors in creating the illusion that “you are there,” though neither is as important as the recording. Or we could leave that last bit out, and just say that ALL THREE are important.

I agree with both sentences. By which I mean to imply that in general my feeling is that the recording is the most important of the three variables, at least with respect to the role that ambient cues play in "you are there" realism.

So in conclusion, I have no conclusion :-). At least, beyond what I've said earlier. But those are some thoughts that come to mind in response to your latest post.

Best regards,
-- Al

Your last post, while of course highly thoughtful, I would have to very respectfully say strikes me as being essentially a set of hypotheses, which are subject to challenge and skepticism in several ways…

Al – You are absolutely correct. Nearly everything in my last post I would consider a hypothesis, not a fact. Looking back at my post, I can see how I failed to make that clear. Usually, I am careful to include lots of phrases like “in my view,” “As I see it,” “I believe that” and so on. In other threads, I have often used the words “hypothesis” and “proposal.” But in my last post, there is a shortage of such words and phrases, which could easily give the impression that I regarded its contents as a group of generally accepted facts. I do not. I was struggling more than usual to organize my ideas, and so certain things got missed. In any case, like you, I regard the contents of my last post as a collection of hypotheses. That is to say, they are proposals about what MIGHT be true, proposals that have some evidence to support them, but that, like all proposals, can be defeated by other evidence. Having said that, let’s look at the evidence…

RE: (1) TIME SCALE DIFFERENCES BETWEEN LISTENING SPACE AND RECORDING SPACE

…there is little reason to expect, in general, that omnidirectional presentation in the listening room will augment or better present the omnidirectional information that was captured in the recording space, because of the vastly different delay times that are involved.

I acknowledge that the time scale differences between the typical recording space and the typical listening space can be quite significant. But I don’t know that those differences warrant much skepticism about my view that the omnidirectional presentation of ambient cues in the listening space helps create the illusion that "you are there."

Here are some of the reasons…

(i). You are quite right that the time scale of the first order reflections in a typical concert hall, being somewhere around 25-40 ms, cannot be reproduced in the listening room, since the listening room would have to be the size of a concert hall. However, a concert hall is the worst cast scenario. Many recording spaces are considerably smaller, to the point where the first order reflections of the recording space might be on roughly the same time scale as the first order reflections of the listening room. So the closer the size of the listening space is to the size of the recording space, the closer the time scales will be, and the less of an obstacle differences in time scale will be to creating the illusion that “you are there.” But even in cases where the listening space is much smaller than the recording space, there are still reasons to believe that the listening space can make a significant contribution to the illusion that "you are there." Which brings me to…

(ii). It seem to me, and this again is a hypothesis, that even when the recording space is so large that it is impossible to construct a listening space whose first order reflections can exist at the same time scale, you can construct a listening space that, in important respects, EMULATES the larger recording space. First, you can absorb the first order reflections of the listening space. This will lengthen the time before reflections reach the listening position, and, in effect, acoustically "enlarge" the listening room. Second, you can reflect or diffuse the second, third, and fourth order reflections of the listening space to provide a SUBSTITUTE for the first order reflections in the recording space. Admittedly, an analysis of the order of reflections would be significantly different between the two spaces. But a listening space that sustains higher order reflections with an amplitude and time scale similar to the lower order reflections of the recording space will, by doing so, RESEMBLE the larger recording space. I believe that kind of listening space allows the ambient cues in the recording to be presented in a way that APPROXIMATES the amplitude, time scale, and directionality of the ambient cues as they sounded in the recording space, contributing to the illusion that ‘you are there.”

(iii). Finally, matching the reverberation time of the listening space to that of the recording space can further enhance the illusion that "you are there." This can be accomplished even when the listening space is rather small and the recording space is rather large. This is another respect in which the differences in time scales involved in different spaces is not an insuperable obstacle to an effort to create the illusion that "you are there" by constructing a listening space that presents ambient cues in a way that approximates the way they were presented in the recording space.

In light of this, it seems to me that the approach to creating the illusion that “you are there” by constructing a listening space that provides the omnidirectional presentation of omnidirectional ambient cues is not defeated by differences in time scales, since (a) the time scales of the listening space are not always radically different from the time scales of the recording space, depending on the type of music; (b) the higher order reflections of the listening space can, to some extent, act as substitutes for the lower order reflections of the recording space; and (c) matching the reverberation time of the listening space and the recording space can be done (nearly) regardless of the size of the recording space. In my view, these measures constitute partial solutions to the limitations imposed by differences in time scales between listening spaces and recording spaces, even when the recording spaces are very large, like concert halls. And because of that, I do not feel that differences in time scales create serious doubts about my view that the omnidirectional ambient cues of the listening space can be used to augment the omnidirectional ambient cues of the recording space, and thereby enhance the illusion that "you are there." Having said that, I acknowledge that differences in time scales is something that must be carefully addressed in the listening room, if you are serious about creating the illusion that "you are there."

It seem to me that part of your skepticism, Al, is focused on my suggestion that, in order to create the illusion that “you are there,” ambient cues must be presented OMNIDIRECTIONALLY. In my last post, I tried to provide several arguments that express why I believe that. What it essentially comes down to is that, in order to create the illusion that “you are there,” the directionality of ambient cues in the listening space must resemble, as much as possible, the directionality of ambient cues in the recording space. And in the recording space, the ambient cues were OMNIDIRECTIONAL. Hence, in the listening space, they must be OMNIDIRECTIONAL. That does NOT mean, however, that the speakers must be omnidirectional (more on this below). Here is a quote from a speaker manufacturer who expresses more or less the same thing I’ve been saying:

…why do anechoic chambers sound so odd and artificial? We are accustomed to hearing the acoustics of the room we are in and spacial cues coming from many directions. Although a recording contains the acoustics of the concert hall, during playback those spacial cues are not coming from the original directions—they are all coming from the two speakers in front of us—very artificial. It is a crude and unnatural way to simulate an acoustic environment. We need to hear those spacial cues coming from all around us. In an anechoic chamber they don't. In contrast, I suspect the reason stereo works as well as it does in our homes is because of room acoustics. In a way, the room reflections are substitutes for the ones we would get at a live event. The reverberant field in our home listening room surrounds us with sound, not as a simulacrum of the actual location of the recording, but as a substitute. Those cues in the recording can then be interpreted as if coming from their original directions.

This is not an appeal to authority. I don’t regard this manufacturer as any particular authority, nor do I necessarily agree with his views on loudspeaker design. It’s just something I found that expresses, in a slightly different way, what I’ve been trying to say.

RE: (2). BIDIRECTIONAL VS. OMNIDIRECTIONAL SPEAKERS

There would certainly seem to be ample empirical evidence, such as in the system descriptions posted here at Audiogon, that high quality directional speakers are not necessarily at a disadvantage, relative to speakers with broad or omnidirectional dispersion characteristics, in creating a reasonably good "you are there" illusion.

I agree with this. In my response to Learsfool in my last post, my point was NOT that omnidirectional speakers are inherently superior to highly directional speakers at creating the illusion that “you are there.” My point was to express doubt about HIS suggestion that highly directional speakers were inherently superior to other designs at creating the illusion that “you are there.” In my view, neither is inherently superior to the other, when considered independent of the listening room. However, I do believe that some speaker radiation patterns will work better than others in PARTICULAR listening rooms.

RE: (3). HEADPHONES

…it seems to me that the major problem with headphones is not that the sound is presented bidirectionally. Per my item 2 above, speakers that present bidirectionally can, at least in many circumstances, present a reasonably good "you are there" illusion.

The bidirectionality of most speaker designs is not equivalent to the bidirectionality of headphones. To state the obvious, once you place bidirectional speakers in a listening room, they create a reverberant sound field. Hence the sound at the listening position is, to some extent, omnidirectional. The only place bidirectional speakers create a completely bidirectional sound field is in an anechoic chamber. In the real world, bidirectional speakers create SOMEWHAT OMNIDIRECTIONAL sound at the listening position. In contrast, headphones always create a COMPLETELY BIDIRECTIONAL presentation. In light of this, the success of bidirectional speakers at creating the illusion that “you are there” is not a reason to believe that headphones can, by virtue of similar directionality, create the illusion that “you are there.” The reason is because the sound field of bidirectional speakers is no longer purely bidirectional, once you put them in the listening room, while headphones remain completely bidirectional, come what may.

I'll add that on normal stereo recordings of classical music, if they are well recorded, minimally mic'd, and minimally processed, I can clearly hear ambient cues and hall effects on my Stax headphones.

Yes, I agree with this, as I mentioned in the last paragraph of my last post. Headphones DO provide ambient cues from the recording. But they do not present them OMNIDIRECTIONALLY, which is how they sounded in the recording space. That is why I don’t believe headphones can create the experience that “you are there” on typically mic’d recordings. Which brings me to...

I have two or three binaural recordings, and they can be truly spectacular in their "you are there" realism, when listened to with headphones.

I have not head a binaural recording through headphones, though I do not doubt, from what I know of the technique, and testimony like yours, that it can create the illusion that “you are there.” So none of my comments about headphones apply to binaural recordings.

Having said that, it seems to me that the success of binaural recordings at creating the illusion that “you are there” SUPPORTS the things I’ve been saying about the importance of the DIRECTIONALITY OF AMBIENT CUES in creating the illusion that “you are there.” Unlike typical recordings, binaural recordings contain robust information about the DIRECTIONALITY OF AMBIENT CUES. That is the reason, I believe, that they can create the illusion that "you are there." For the vast majority of recordings, which are not binaural, the directionality of ambient cues must somehow be recreated IN THE LISTENING ROOM, if you want to create the illusion that "you are there." Or that is my hypothesis, anyway. :)