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


Sometimes a system sounds like "they are here." That is, it sounds like the performance is taking place IN YOUR LISTENING ROOM.

Sometimes a system sounds like "you are there." That is, it sounds like you have been transported to SOME OTHER ACOUSTICAL SPACE where the performance is taking place.

Two questions for folks:

1. Do you prefer the experience of "they are here" or "you are there"?

2. What characteristics of recordings, equipment, and listening rooms account for the differences in the sound of "they are here" vs. "you are there"?
bryoncunningham

Showing 24 responses by bryoncunningham

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.

Yes, Al, I did miss this when responding to your post. Don’t know why. If I understand you correctly, you are saying that, if you construct a reactive listening space with an omnidirectional sound field, that omnidirectional sound field will include both the DIRECT and the INDIRECT sound from the recording space. In other words, some of the sound that was DIRECT in the recording space is now INDIRECT in the listening space, which is, strictly speaking, an INACCUATE ambient cue. If that is the “tradeoff” you are referring to, then…

In my view, it is a worthwhile tradeoff. I believe that the value of providing a listening space in which ambient cues can arrive at the listening position omnidirectionally outweighs the value of hearing the exact ambient cues on the recording without the addition spurious ambient cues created by the listening space. The criterion for that judgment is: Which is more valuable to creating the illusion that “you are there”?

In other words, OMNIDIRECTIONAL ambient cues are more valuable than STRICTLY ACCURATE ambient cues for creating the illusion that “you are there.” I believe that headphones (in the absence of a binaural recordings) illustrate that, in that headphones will give you the most ACCURATE sound of the ambient cues of the recording, but not an OMNIDIRECTIONAL presentation of those cues. The result is the ABSENCE of the illusion that "you are there."

In my view, if you value accuracy above all else, then listening through headphones or in an acoustically inert room is superior. But if you value the experience that “you are there,” then listening in a room that supports omnidirectional ambient cues is superior, even if some of those ambient cues do not exist on the recording. This is an especially worthwhile tradeoff if the spurious ambient cues created by the listening space RESEMBLE the kinds of ambient cues created by the recording space. This brings me to…

…listening rooms do not come anywhere near capable of recreating the original recording space, if this space is a concert hall (or a good jazz club, for that matter) - so this means that the listening space will ALWAYS be fundamentally different from the recording space…

Learsfool – I think you slightly overstate the case here, but the general point that you are making is one that I have acknowledged throughout this thread. That is to say, constructing a listening space that CLOSELY resembles certain recording spaces can be nearly impossible, unless we were all very rich men. However, that does not mean that we must abandon the concept of resemblance altogether. To me, the listening space can still APPROXIMATE the recording space in ways that enhance the illusion that “you are there.” I mentioned some ways in a previous post.

Admittedly, a close approximation may require more architectural design and more acoustical treatment than most of us can afford, but I believe that audiophiles can learn lessons from great listening rooms in order to improve their own listening rooms, even if it is only on a very modest scale. As it turns out, many of the features that make a listening room great are available to the thrifty audiophile in a more modest version, if he has the inclination to try.

Incidentally, I am not holding myself up as a exemplar of conscientiousness about listening room acoustical design. Hardly. But I have the belief that it is The Great Frontier for audiophiles. That goes for me, and frankly, for most A’gon folks, judging from the virtual systems on this site.
Thanks for the responses. The majority of posters so far have a preference for the experience of "you are there." I have a pet theory about what creates that experience:

Whether a system sounds like “they are here” or “you are there” is principally determined by AMBIENT CUES during playback. The presence/characteristics of ambient cues during playback is itself largely determined by the following, in descending order of importance:

(1) RECORDING: Ratio of direct to reflected sound.

(2) LISTENING ROOM: Resemblance to the recording space.

(3) EQUIPMENT: Relative neutrality or coloration.

RE: (1) RECORDING. Recordings that contain ambient cues are more likely to provide the experience that “you are there.” Those that lack them are more likely to provide the experience that “they are here.” The presence of ambient cues is mostly a consequence of the ratio of direct to reflected sound contained in the recording.

The ratio of direct to reflected sound is itself largely a consequence of microphone type and placement: The (a) more directional the pickup pattern of the microphone; and (b) the closer the microphone is placed to the acoustical event, the higher the ratio of direct to reflected sound on the recording. The (a) less directional the pickup pattern of the microphone; and (b) the farther the microphone is placed from the acoustical event, the lower the ratio of direct to reflected sound on the recording.

Since ambient cues about the acoustical environment are disproportionately contained in the reflected sound, recordings that have a lower ratio of direct to reflected sound will have more ambient cues, and consequently, sound more like “you are there.”

RE: (2) LISTENING ROOM. Listening rooms that resemble the recording space are more likely to provide the experience that “you are there.” That is because, when the listening room resembles the recordings space, they have similar ambient cues. As a result, the ambient cues of the listening room will naturally augment the ambient cues of the recording space contained in the recording, enhancing the experience that “you are there.”

Resemblance is a matter of size, shape, quantity/placement/ratio of absorption and diffusion, reverberation time, and so on. The more your listening room resembles the recording space in each of those characteristics, the more it will sound like “you are there.”

RE: (3) EQUIPMENT. Equipment that is neutral, in the sense of ‘degree of absence of coloration’ is more likely to provide the experience that “you are there.” That is because colorations frequently conceal, corrupt, or eliminate the ambient cues of a recording, thereby reducing the experience that “you are there.”

Some colorations, it could be argued, add “ambient cues” of the own, thereby increasing the likelihood of the experience that “you are there.” I have doubts about this, since the “ambient cues” added by colorations are largely constant, whereas the ambient cues of recording spaces are infinitely variable. Hence the chances of the two resembling each other across a wide range of recordings seems unlikely. Therefore, colorations that add "ambient cues" of their own may often enhance the experience that "you are somewhere," but seldom that "you are there."

Fire away.
I say that because of the different time scales that are involved. Given that sound propagates through air at roughly one foot per millisecond, the arrival times at the listener's ears of wavefronts that are launched from non-aligned speaker drivers would most likely differ by less than a millisecond. While reflected sound in a hall typically arrives at the microphones many milliseconds after the direct sound.

Good point, Al.
Cbw – I have reread your posts in an effort to construct an argument that expresses your objection. Here is my best guess…

(Cbw-1) Increasing some colorations, like brightness, increases the audibility of ambient cues in the recording.

(Cbw-2) Increasing the audibility of ambient cues in the recording enhances the illusion that “you are there.”

(Cbw-3) Therefore, increasing some colorations enhances the illusion that “you are there.”

(Cbw-4) Therefore, increasing neutrality does not always enhance the illusion that “you are there.”

If this argument expresses your objection, then I think your conclusions are correct, but those conclusions don't constitute an objection to my views. While increasing neutrality may not ALWAYS enhance the illusion that "you are there,” in my view, it USUALLY does. To see this, it’s first necessary to look at premise (Cbw-2)...

RE: (Cbw-2). As I mentioned in a previous post, increasing the audibility of ambient cues from the recording does not NECESSARILY enhance the illusion that “you are there.” In other words, ambient cues BY THEMSELVES are not a sufficient condition for creating the illusion that “you are there.” There are other conditions necessary for creating the illusion that “you are there.” For example, a certain degree of transparency. In my view, colorations that grossly distort a recording in order to emphasize ambient cues probably won’t increase the illusion that “you are there,” since those gross distortions are likely to diminish the illusion that “you are there” in other ways – for example, by reducing transparency.

You may be thinking, “Instead of colorations that GROSSLY distort a recording, what about colorations that SLIGHTLY distort a recording?” In other words, could a small amount of coloration, just enough to emphasize ambient cues, but not enough to significantly reduce transparency, enhance the illusion that “you are there.” I believe the answer to this is: Possibly. This is where, I agree, things become subjective. Whether a small increase in ambient cues at the expense of a small decrease in transparency has the net result of enhancing or diminishing the illusion that “you are there” is probably a judgment that varies from listener to listener. But none of this casts doubt on my view that, USUALLY, reducing colorations enhances the illusion that "you are there." The reason is because reducing colorations tends to increase RESOLUTION. Which brings me to...

Regarding the issue of my “information theoretic” approach to resolution, my view is that resolution can be understood as “information about the music.” If you combine this with my suggestion that increasing resolution increases ambient cues, then you get: Increasing information about the music increases ambient cues, which is something I think is self-evident. But none of this entails that more information, BY ITSELF, is a sufficient condition for enhancing the illusion that “you are there.” As I’ve stated in previous posts, creating the illusion that “you are there” is not reducible to ambient cues. I would now add: It is not reducible to resolution. And it is not reducible to information. Hence, when you say, regarding my definition of resolution in terms of information…

…you would get vastly more information by dumping the low frequencies entirely in favor of enhancing the highs -- you'd maximize the information about the music, but the result wouldn't be music. So I think some other definition is in order.

It does not matter if “dumping low frequencies” would “maximize the information about the music,” (a point about which I am skeptical), because creating the illusion that “you are there” is not reducible to maximizing information, just as it is not reducible to resolution, or ambient cues. In my view, the resolution of (i.e. information about) ambient cues is the PRINCIPAL, but not the only, determinant of the illusion that "you are there." That is why I have spent so much time talking about ambient cues.

Returning to the issue of equipment colorations…

I acknowledge that SOME equipment colorations might enhance the illusion that “you are there.” This is a corollary to the point I made about listening rooms on 9/5, namely, that the illusion that “you are there” might be enhanced when the colorations of the listening room RESEMBLE the colorations of the recording space.

But the problem with relying on room colorations to enhance the illusion that "you are there" is that, while the colorations of recording spaces are infinitely variable, the colorations of listening rooms are largely constant. So even if the colorations of the listening room enhance the colorations of some recordings, they are likely to detract, confuse, or obscure the colorations of other recordings.

A similar problem arises for the use of EQUIPMENT colorations to enhance the illusion that "you are there." While the colorations of recording spaces are infinitely variable, the colorations of any given component are largely constant. So even if the colorations of a component enhance the colorations of some recordings, they are likely to detract, confuse, or obscure the colorations of other recordings.

I believe this limits the effectiveness of using colorations, whether in equipment or in listening rooms, to enhance the illusion that “you are there.” Another drawback, equally significant, to the use of colorations to enhance the illusion that “you are there” is that colorations tend to diminish resolution, and less resolution means less audible ambient cues from the recording itself.

In light of all this, I believe that the practical approach for the audiophile who listens to a wide range of music is to (1) minimize colorations both in the equipment and in the listening room; and (2) increase information about the music, to the extend that is possible. In other words, enhancing the illusion that "you are there" is, with a few possible exceptions, most practically achieved by increasing neutrality and increasing resolution.
Hi Al. Thanks for your comments. Some thoughts…

The one exception I would take concerns item no. 2. I doubt that it is typically possible for the acoustics of the listening room to resemble those of the recording space in any meaningful way (assuming the recording space is a hall), because the dimensions (and hence the delay times between direct and reflected sound) are so vastly different.

To a large extent, I agree with this. Item (2) - the idea that resemblance between the listening room and the recording space enhances the illusion that “you are there” - was intended to describe a correlation that is largely theoretical. In the real world, the listening room rarely resembles the recording space, except in a very approximate way. As you point out, this is especially true for certain kinds of recording spaces, such a halls.

Having said that, I would stop short of concluding that it is impossible for the listening room to resemble the recording space “in any meaningful way.” It seems to me that sometimes the listening room can resemble the recording space in a meaningful way, in the sense that there are characteristics of the listening room that, to the extent that they approximate the recording space, will contribute to the illusion that “you are there.” For example…

Imagine for the moment that your preference in classical music were confined to orchestral music. In that case, I believe that you would be more likely to create the illusion that “you are there” with a large listening room with a high level of diffusion and a medium to long-ish reverberation time. In contrast, Cbw723’s preference for “studio-recorded material” would be better served with a medium or small sized listening room with plenty of absorption and a comparatively short reverberation time ("acoustically dead," as he describes it). In either case, the resemblance of the listening room to the recording space is only a very rough approximation. But it seems to me that it is a meaningful approximation, in the sense that it will contribute to the illusion that “you are there.”

Of course, all this assumes that the system is playing back recordings with similar recording spaces. In reality, most people listen to a wide range of recordings with vastly different recording spaces. Because of that, I completely agree with your view that, for the audiophile who listens to a wide range of music...

…the overall combination of room acoustics and equipment should be as neutral as possible, to make the listening experience as "you are there" as possible.

My view is that...

1. If an audiophile listens predominantly to one type of music, he should design his listening room (when possible) to approximate the typical characteristics of the recording spaces for that type of music, so as to promote the illusion that "he is there" for the music he usually listens to.

However...

2. If an audiophile listens to a wide range of music, he should design his listening room (when possible) to be neutral, so as to promote the illusion that "he is there" for as many kinds of recording spaces as possible, acknowledging that the more neutral the room, the less likely it is to approximate the recording space of any particular type of music.
In situations where the ambience cues are subtle or absent, having room reinforcement would likely be beneficial. But in cases where the cues are already strong, reinforcement could become excessive.

Cbw – This is a good point. To the extent that the ambient cues of the listening room resemble those of the recording space, playback in the listening room will reinforce the ambient cues of the recording. It is certainly possible that, for some recordings, that reinforcement could be excessive. In the worst case, the ambient cues of the listening room would, in effect, "double" the ambient cues of the recording. In light of this, designing a listening room with the intention of reinforcing the ambient cues of one type of recording space must be approached judiciously.

…with weak or absent cues, and hard-to-duplicate room acoustics, electronic enhancement may be the way to go.

The idea of creating listening room ambience by electronic means is appealing in theory. In practice, however, the limited experience I have had with professional reverb processors from high end manufacturers was not favorable. Although they were much better at creating ambient cues than the DSP processing typically found in consumer components, they were nevertheless, to my ears, artificial sounding. Because of that, I am skeptical of the electronic approach to creating ambience, at least with the current state of technology. I have far more confidence in the results of controlling ambient cues through listening room design.

I'm not sure how much the playback system's coloration is an issue. Assuming the system is good enough to produce playback with a convincing live or nearly live sound (as judged by the system's owner/primary listener), it seems unlikely that the ambience cues are going to be distorted to a point that they become an impediment to a "you are there" experience.

I agree that the equipment is less important than either the recording or the listening room in determining ambient cues during playback, as I indicated in the “descending order of importance” in the OP. However, I believe that colorations in equipment can be a real obstacle to the presentation of ambient cues during playback. I became convinced of this when making component changes in my own system that simultaneously resulted in (1) greater neutrality, judged by independent criteria; and (2) greater audibility of the ambient cues of recordings.
Some colorations may enhance the cues. Excessive brightness comes to mind. You get lots of detail in bright systems -- to the point that the ambience cues will practically jump out of the speakers and punch you in the head -- but such systems are not particularly neutral (though they are preferred by some listeners).

Cbw - This is an interesting point, and one that had not occurred to me. I think you may be right that some equipment colorations, like brightness, might enhance ambient cues, at least from a psychoacoustic standpoint.

But I wonder whether those colorations would contribute to the illusion that “you are there.” My suspicion is that the answer is often 'no.' That is to say, colorations that enhance ambient cues might nevertheless fail to contribute to the illusion that “you are there” because they might also make the music sound less “real.” I, for one, have a hard time experiencing a bright system as one in which “I am there.” In other words, I suspect that whatever gains are made by colorations that enhance ambient cues might be offset by the system sounding less real. And the less real a system sounds, the harder it is to believe that “you are there.”

All this highlights the fact that ambient cues, while a NECESSARY condition for creating the illusion that “you are there,” are not a SUFFICIENT condition. I have focused on ambient cues throughout this thread because I believe that they are the PRINCIPAL determinants of the illusion that “you are there.” The ambient cues of the recording are the most important, followed by the listening room, followed by the equipment. Which brings me to...

My view about equipment colorations and ambient cues:

Equipment colorations tend to conceal, corrupt, or eliminate ambient cues, though there may be some colorations that enhance ambient cues, at least psychoacoutically. But colorations that enhance ambient cues do not necessarily contribute to the illusion that “you are there,” for the reasons stated above.

Rather than relying on equipment colorations to enhance ambient cues, it seems to me that there is far better way to hear the ambient cues on a recording, and thus to contribute to the illusion that “you are there,” and that is by increasing RESOLUTION.

Increasing resolution is not the same thing as increasing “perceived detail,” since the latter may be increased, as you pointed out, by changing a system’s frequency response (i.e. making the system brighter). Increasing resolution is a matter of increasing either (1) format resolution, or (2) equipment resolution. Which brings me back to my view on the relation between equipment colorations and ambient cues...

I believe that equipment colorations tend to reduce equipment resolution, and hence to obscure ambient cues. Conversely, the reduction of colorations tends to increase resolution, thereby increasing the perceptibility of ambient cues and contributing to the illusion that “you are there.”
I also agree with those near the beginning of the thread (I think Newbee was one) who stated that the recording itself is the very biggest factor in creating a "you are there" experience - a far bigger factor than these other factors under discussion for most of the thread.

I was one of the people who suggested this earlier in the thread. In my view, the illusion that "you are there" is created by ambient cues during playback. The biggest determinant of ambient cues during playback is the recording. Then the listening room. Then the equipment.

I suspect the reason so much discussion has focused on listening rooms and equipment is because the characteristics of recordings are outside the audiophile’s control, except in the sense that he can make an effort to find recordings with interesting ambient cues, as Al pointed out. On the other hand, listening rooms and equipment are inside the audiophile’s control. So, while they have a lesser role in creating the illusion that “you are there,” discussions about them may lead to conclusions that are more actionable.

It is simply not a high priority for most engineers now to recreate the actual sound of the hall. The engineer…adds digital reverberation to create a false ambience…

As you seem to imply, recordings of this kind DO contain ambient cues, but they are not ambient cues of REAL recording spaces. They are ambient cues of VIRTUAL recording spaces. I suppose there is no reason why, in theory, a virtual recording space couldn’t be as interesting as a real one. In practice, the best recording spaces I have heard have always been the real ones. So it is regrettable that they are becoming less and less common.

I want to hear what that orchestra sounds like IN THAT SPACE…For me, [there] are much more important traits for a system than "neutrality," though I don't propose to start that discussion all over again. I am merely trying to explain why musicians place such a high priority on soundstaging and imaging. They are crucial to creating a "you are there" experience.

I agree that, for many recordings, creating the illusion that “you are there” greatly enhances the listening experience. I also agree that soundstaging and imaging are crucial to creating the illusion that “you are there.”

However, I believe that soundstaging, imaging, and the illusion that "you are there" are all connected to the characteristic of neutrality. I am hesitant to mention this, because I don’t want us to get trapped back on the infinite staircase of our neutrality discussion. So, leaving the term ‘neutrality’ out of it, and using the somewhat less controversial term ‘coloration,’ I would say that many colorations diminish the illusion that “you are there.” Here is an argument that expresses one of the reasons why:

(1) Decreasing colorations tends to increase resolution.

(2) Increasing resolution increases the audibility of ambient cues in the recording.

(3) Increasing the audibility of ambient cues in the recording enhances the illusion that “you are there.”

(4) Therefore, decreasing colorations tends to enhance the illusion that “you are there.”

(5) Therefore, increasing colorations tends to diminish the illusion that “you are there.”

There are various qualifications and exceptions I would make to the argument above, but it captures the spirit of my view.
One more thing about binaural recordings…

While binaural recordings, literally speaking, are bidirectional, they nevertheless RECREATE the same information that results from the OMNIDIRECTIONAL arrival of ambient cues. That is precisely the point I have been trying to make about the listening room, namely, that it must RECREATE, to whatever extent possible, the same information that results from the OMNIDIRECTIONAL arrival of ambient cues, if it is to create the illusion that “you are there.”

Now I will pause for a brief resumption of my life.
Al wrote:

…a very key factor seems to me to be what might be referred to as resolution in the time domain.

I completely agree with this. Though I failed to mention it, the same thing occurred to me during my discussion with Cbw about FREQUENCY response, which I believe is less important than TRANSIENT response when it comes to the retrieval of ambient cues that create the illusion that “you are there.”

A notable example would be a speaker having sloppy transient response, whose output tends not to stop as immediately as it should when a sharp transient concludes. Such a speaker will tend to obscure the reflected energy that had been picked up by the microphones some tens of milliseconds after the arrival of the directly captured sound.

In light of this, I wonder whether, as a generalization, speaker designs that emphasize time-alignment are better at presenting ambient cues, all other things being equal. Do you think so?

…perhaps the reason such a [large] room would enhance the "you are there" illusion for classical music is not because its large dimensions produce room reflections that begin to mimic those of the hall (which in turn is far larger still), but rather because its large dimensions REDUCE the amplitude of those reflections, as heard at the listening position, thereby reducing the degree to which room acoustics obscure our ability to hear the reflected energy that the mics had captured.

This is an interesting thought. When considering the value of a large listening room, I was thinking of the fact that larger rooms tend to have longer reverberation times, and hence the ambient cues of the listening room might naturally augment the ambient cues of recordings with large recording spaces. But you are certainly right that the AMPLITUDE of reflected sound at the listening position is just as important as the DURATION of reflected sound (i.e. reverberation time) in the listening room. Hence there seem to be two competing strategies for the presentation of a recording's ambient cues:

(i) The use of ambient cues of the listening room to augment the ambient cues of the recording.

(ii) The minimization of ambient cues of the listening room so as to reveal the ambient cues of the recording.

Since (i) will be helpful only for those who listen to recordings with similar recording spaces, (ii) is probably the more practical approach for most audiophiles.

Onhwy61 wrote:

IMO the original question is another example of overstating the importance of soundstage/imaging in high end audio.

If you look again at the OP, you will see that I didn’t say anything about the importance of creating the illusion that “you are there” relative to any other audiophile goal. In fact, in my subsequent posts, I haven’t even expressed a preference for the experience that “you are there” over the experience that “they are here.” The reason is because I enjoy both, depending upon the type of music, the quality of the recording, and the characteristics of an audio system, especially the listening room.

In addition, my comments have not been about soundstage and imaging. They have been about AMBIENT CUES, with respect to recordings, listening rooms, and equipment. The discussion of ambient cues is not equivalent to the discussion of soundstage/imaging, since the former is a considerably broader topic than the latter. For example, ambient cues on recordings can be heard through headphones, where soundstage and imaging are a non-factors.

As a practical matter very few recordings actually have real ambient cues. This is true even in classical recordings. The current trend in studio recordings is to completely suppress the acoustics of the recording site and to synthetically create an ambiance at a later stage in the recording chain. Literally there's no real there to be transported to.

I am aware of this regrettable fact. Current recording trends being what they are, many (perhaps most) recordings do not contain ambient cues of REAL recording spaces. They do, however, contain ambient cues of VIRTUAL recording spaces, added during mixing. You may feel that a virtual recording space is not one worth visiting, and hence the effort to create the illusion that “you are there” for such recordings is a waste of time. I have some sympathy for that point of view. But I do think that some virtual recording spaces are worth visiting. Think: Pink Floyd. I also agree with Al that recordings that contain ambient cues of real recording spaces are out there to be found, though it takes some looking.

Cbw wrote:

If you define resolution in purely technical terms, then you could increase the resolution of your source, and thereby your system, but that could have no audible result (because, for example, the signal-to-noise ratio of your overall system may be the limiting factor). So "resolution" then says something about your gear, but nothing about your sound, and is therefore disconnected from realism, ambience cues, and the "you are there" experience.

I do not think of resolution this way, and I don’t think most audiophiles do either. The term ‘resolution’ is used by audiophiles to describe both a characteristic of an individual COMPONENT and a characteristic of a whole SYSTEM. Hence the term ‘resolution’ says something about how a system sounds. I am not claiming ownership of the term ‘resolution.’ I am expressing what I believe to be the prevailing use of the term among audiophiles. For the purposes of this discussion, I will stipulate a definition of ‘resolution’: The absolute limit of information about the music that a format, component, or system can present.
You kind of make my point while simultaneously avoid addressing it.

I must confess, I do not get your point. What is it?
Hi Learsfool. Your initial comments about the role of mixing are well taken. Onhwy61 brought up something similar when he pointed out that many recordings have no real ambient cues, but only "synthetic" ambient cues added during mixing. Al and I both posted some thoughts about that regrettable fact, which you may find relevant, when you get a chance to look.

Glad that you are joining the discussion.
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.”
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.”
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. :)
I am doubtful that on non-binaural recordings headphones can be said to give an accurate reproduction of ambient cues, or anything else, because of the fact that they bypass the pinnae, and inject the sound from the sides instead of from the front.

This is a good point, Al. I should have chosen an anechoic chamber rather than headphones to illustrate my view that omnidirectional ambient cues are more valuable than strictly accurate ambient cues for creating the illusion that “you are there.”

On a side note, how do you edit a post after it’s been posted? Can you give me a link to instructions here on A’gon?

Dgarretson – Glad that you joined in. I had never heard of the crossfeeding process you describe. I would love to hear it some day. Connecting it to this discussion, I would say that, like binaural recordings, it once again illustrates the importance of the DIRECTIONALITY of ambient cues for creating the illusion that “you are there.”

Cbw – Wow! A lot of great thoughts and insights.

Consider doing the playback in exactly the same space as the recording. You set up the speakers and the equipment to optimally reproduce the soundstage, and put the listener in the position of the microphone that recorded the performance. Thus, your listening space exactly reproduces the recording space. Is this the optimal space for creating the “you are there” experience? I don’t think so…

The real goal in this approach is not to PHYSICALLY replicate the recording space, but rather to approximate it in some important ACOUSTICAL parameters, including: relative balance of direct and indirect sound, relative balance of reflected/diffused/absorbed sound, time delay of first indirect sound, reverberation time, and so on. Optimizing these acoustical parameters of the listening space so that they have values that approximate those of the recording space is the kind of “resemblance” I have in mind. I should probably drop the word “resemblance” altogether from this discussion, because it does conjure up images of physical likeness. I should stick to words like “emulate,” to avoid the idea that this approach is about PHYSICAL resemblance. It’s not. It’s about ACOUSTICAL resemblance.

You are quite right to point out that acoustical resemblance during playback cannot be achieved simply by creating a facsimile of the recording space. Creating an acoustical resemblance between the listening space and the recording space takes into account things like the number of sound sources in the listening room (two, assuming you are listening in stereo) and the position of the listener relative to those sources and to room boundaries. It also takes into account a host of other variables, the manipulation of which, with any luck, results in a listening space that acoustically emulates the recording space, at the listening position. With that in mind...

The various kinds of room colorations you mention, what you are calling “source distortion,” “echo distortion,” and “temporal distortion,” are definitely things to be addressed. But it seems to me that these are precisely the kinds of things that an acoustically treated room DOES address. “Source distortion” is typically addressed by absorption or diffusion at the first order reflection points on the side walls and the ceiling. “Echo distortion” is typically addressed with diffusion behind the speakers. “Temporal distortion” is typically addressed by balancing the ratio of absorption to diffusion to achieve a specific reverberation time.

In light of this, I do not believe that the various kinds of distortion you mention are, in themselves, reason to believe that this approach is doomed to failure. IF this approach were tantamount to constructing a listening space that was a PHYSICAL replica of the recording space, then I would agree with you that it would be doomed. But the approach is to construct a listening space that, in important ACOUSTICAL respects, emulates the recording space, AS HEARD FROM THE LISTENING POSITION. It seems to me that that approach is not doomed to failure, though it is certainly bounded by constraints, both practical and theoretical.

So you have a range of recordings (from heavy cues to none), and a range of rooms (from live to dead), but it doesn’t seem possible to have an optimal room for both ends of the spectrum (which I think you’ve said)…

I agree that it is not possible to have an optimal room for all recordings. A person must choose on the basis of the recordings they tend to listen to, or the ones they are the most interested in optimizing, for whatever reason.

To sum up, I think to the extent that you succeed in making the ambience cues from the recording omnidirectional, they’ll be mis-timed, out of phase, and probably polarity flipped. And that is on top of all of the very strong room cues that you will necessarily generate to get the recorded cues to be omnidirectional. Or, to put it another way, I don’t think it is possible to get the recorded cues to be omnidirectional without seriously compromising the “you are there” effect.

This is an interesting argument. As I understand it, you are saying that the measures required to create omnidirectional ambient cues in the listening space would, in effect, destroy the accuracy of the ambient cues of the recording, as heard at the listening position. In a way, you are saying what Al said in point (3) of his post from 9/13 - what he described as a “tradeoff.” So my response to your argument is the same as my response to his observation: My view is that omnidirectional ambient cues are more valuable than strictly accurate ambient cues for creating the illusion that "you are there." Having said that, I guess I’m not as skeptical as you, Cbw, about the possibility of constructing a listening space whose acoustics allow for omnidirectional ambient cues that are REASONABLY ACCURATE to the recording. I wish I had the resources to build some rooms and put these theories to the test!

So, my theory:
1) Strong recorded cues + live room = a mess tending toward “they are here”
2) Strong recorded cues + dead room = “your are there” but bidirectional cues
3) Weak recorded cues + live room = “they are here” but if the room is sufficiently like the recording space, you approximate “you are there” for that space
4) Weak recorded cues + dead room = “they are here” (or in a studio)

Now this is a nice way of organizing things! But I don’t agree with it all. I think you are absolutely correct about scenarios (3) and (4). But, as I've indicated above, I don’t think category (1) would necessarily result in the “mess” you anticipate, provided that careful attention were paid to acoustical design. I am also doubtful that scenario (2) would result in the illusion that “you are there,” for the reason I have stated many times in this thread, namely that I don’t believe the bidirectional presentation of ambient cues can create the illusion that "you are there." In effect, scenario (2) is an approximation of an anechoic chamber, and I don’t believe you can create the illusion that “you are there” under those conditions.

Having said all this, I should reiterate something I mentioned earlier in this thread, but that may have been lost in the discussion by now: I don't believe that constructing a listening space that emulates a particular recording space is the BEST approach to building a listening room, for many of the reasons that have been pointed out, and some that have not. I do believe that it is a VALID approach, especially for audiophiles who tend to listen to one type of music. For folks who listen to a wide range of music with vastly different recording spaces, constructing a listening space that emulates a particular recording space is probably NOT the best approach. In the latter case, the best approach is probably a balance of:

(1) Emulation of some set of recording spaces.
(2) Creation of a listening space that provides a balance of attributes important for the hearing exactly what is on the recording.

To the extent that an audiophile chooses (1), he is favoring colorations over accuracy. To the extent that he chooses (2), he is favoring accuracy over colorations. (1) is the approach of some audiophiles who are primarily interested in creating a playback space that they themselves find interesting; (2) is the approach of recording studios, where accuracy is the Order of the Day.

The use of the word "coloration" above is not pejorative. Although I am an outspoken (read: notorious) advocate of the absence of colorations in equipment, I have a much more mixed view of colorations in the listening room. Although many listening room colorations are destructive (think: room modes, flutter echo, comb filtering, etc.), some room colorations, I believe, are beneficial. Among other things, they can enhance the illusion that "you are there."
A brief interruption to say a few words about the nature of this thread...

As Al pointed out several posts back, this thread is full of speculation. I myself have speculated at a furious rate. I just want to say that I do not regard speculation as great way to reach reliable conclusions. I regard carefully controlled TESTING as a great way to reach reliable conclusions. In that sense, I am an empiricist.

Unfortunately, I cannot currently afford to build a highly customized listening room, like some of the ones posted here on A’gon. In light of that, I am left to speculate on the basis of my experiences with (1) customized listening rooms for professional mixing; (2) customized listening rooms at audio dealers; and (3) my own quite humble listening room.

The purpose of this post is to explicitly acknowledge that I do not believe that speculation can ever be an adequate substitute for carefully controlled testing. Having said that, not all speculation is groundless. Speculation can be grounded on prior experiences, theoretical knowledge, and sound reasoning. I have made an effort to ground my speculations, though that may not always be apparent, which is my own fault. My thanks to other posters who, it seems to me, have made an effort to do likewise.

It would be nice if some folks with extensive experiences with customized listening rooms or expertise in acoustics would chime in, as it would elevate some of our speculations to the level of highly informed or even expert opinion.

Until that happens, let the speculation continue.
Cbw – I have been giving more thought to your theory, and I have some fresh speculations…

You mention two parameters that determine whether a playback space creates the illusion that “you are there” or “they are here,” namely whether a recording has ambient cues or not, and whether the listening room is “live” or “dead.” To these, I think it’s useful to add a third parameter, namely, whether or not the listening space is acoustically similar to the recording space. With that in mind, I think there are…

FIVE SIGNIFICANT CATEGORIES:

(1) reactive room, ambient recording, acoustical similarity

(2) reactive room, ambient recording, acoustical dissimilarity

(3) reactive room, non-ambient recording

(4) unreactive room, ambient recording

(5) unreactive room, non-ambient recording

SOME DEFINITIONS TO GO WITH THEM:

-“reactive room” is a listening space with significant ambient cues. Hence a listening space that significantly interacts with the ambient cues of the recording during playback. A.k.a., a “live room.”

-“unreactive room” is a listening space with insignificant or no ambient cues. Hence a listening space that minimally interacts with the ambient cues of the recording during playback. A.k.a., a “dead room.”

-“ambient recording” is a recording that contains ambient cues of the recording space.

-“non-ambient recording” is a recording that does not contain ambient cues of the recording space.

-“acoustical similarity” refers to the acoustical similarity of the listening space to the recording space, as discussed in my second post from 9/14.

Each of the parameters that define the five categories is a continuum. A room is not either reactive or unreactive. Reactivity is a continuum, with maximally reactive rooms at one end and minimally reactive rooms at the other. Likewise for ambient cues on recordings. Likewise for the acoustical similarity of the listening space to the recording space. Since each parameter is a continuum, the five categories that they define are each idealizations, in the sense that actual members of each category will APPROXIMATE its idealized description.

Taking the five categories one at a time…

(1) reactive room, ambient recording, room similarity =

…YOU ARE THERE...

In my view, this maximizes the illusion that “you are there,” as I have suggested in earlier posts. I acknowledge, however, that this is not the most practical approach to building a listening space, since the greater the acoustical similarity the listening space has to the recording space, the LESS acoustical similarity it will have to different recording spaces, and the more your listening space will be “recording-specific.”

(2) reactive room, ambient recording, room dissimilarity =

…YOU ARE CONFUSED…

In my view, this would be the “mess” that Cbw was describing in his last post. To the extent that the ambient cues of the listening space are different from the ambient cues of the recording space, it could result in a confused, contradictory, or paradoxical set of ambient cues at the listening position. In other words, “you are confused.”

(3) reactive room, non-ambient recording =

…THEY ARE HERE…

In my view, the absence of ambient cues in the recording combined with a reactive listening space is what creates the illusion that “they are here.” This is perhaps the most straight forward of the five categories. And in some ways, it is the easiest type of illusion to create. Of course, if you don’t like the sound of your listening room, then you won’t like the way “they” sound when “they are here.”

(4) unreactive room, ambient recording =

…YOU ARE “ALMOST” THERE…

This is the trickiest of the five categories, I think. As I have argued in previous posts, I don’t think that you can fully create the illusion that “you are there” without omnidirectional ambient cues at the listening position. So, as a listening room becomes less and less reactive, I believe it will sound less and less like “you are there.”

Having said that, I should acknowledge that this comes close to creating the illusion that “you are there.” The bidirectional presentation of the ambient cues of the recording provides some significant information about the recording space, though as I have argued, it doesn’t present that information with the correct DIRECTIONALITY, which limits the illusion that “you are there.”

Of course, all this assumes that the playback is stereo. If playback were multichannel, then an ambient recording played back in an unreactive room could, in theory, create the illusion that “you are there." I say “in theory” because, as other posters have pointed out, most multichannel music mixes leave much to be desired, and hence typically fail to create the illusion that “you are there.” Nevertheless, the multichannel playback of ambient recordings in unreactive rooms to create the illusion that “you are there” is the prevailing methodology in movie sound, where it achieves some success, I think.

I should also acknowledge that there is a significant advantage to a SOMEWHAT UNREACTIVE listening room when playing back ambient recordings, namely, that it prevents your listening room from being “recording-specific.” But I don’t think that’s the ONLY way to prevent your listening room from being recording-specific (More on that in a future post).

(5) unreactive room, non-ambient recording =

…YOU ARE NOWHERE…

In my view, the absence of ambient cues in both the recording and the room creates an otherworldly “you are nowhere” effect, like you’re listening in outer space (yes, I know that’s impossible).

This may seem like a revision to what I said in my last post, when I agreed with Cbw that the category of “weak recorded cues + dead room” would result in the illusion that “they are here.” But I suspect that, when Cbw was referring to dead rooms, he was not referring to COMPLETELY dead rooms. Hence my earlier agreement with him that partially dead rooms (thus partially reactive) could create the illusion that “they are here.” I am now saying that, to the extent that a room is unreactive, non-ambient recordings will create the experience that “you are nowhere.”
My point was mostly about the difficulty of getting the cues on the recording to be omnidirectional. If you achieve it, I think you also get a whole bunch of extra stuff from your room that you probably don’t want and would likely swamp the recorded cues.

Cbw – I think this is a possible outcome, but, as I mentioned in an earlier post, I am somewhat more optimistic about the possibility of constructing a listening space whose acoustics allow for omnidirectional ambient cues at the listening position that are reasonably accurate relative to those on the recording.

If I understand you correctly, I think you are saying that one can, effectively, simulate ambience cues that approximate the cues on the recording, but are not sourced from the cues on the recording.

Actually, that’s not what I was trying to say, though that’s a reasonable interpretation of what I wrote. Looking back, I can see that what I wrote was ambiguous. I was trying to talk about the ambient cues that ARE, as you put it, “sourced from the recording.” So what I meant was that…

I am more optimistic about the possibility of constructing a listening space whose acoustics allow for reasonably accurate omnidirectional ambient cues, sourced from the recording and audible at the listening position.

Having said that, as I discussed from my post on 9/11, the ambient cues during playback will always be a COMBINATION of the ambient cues of the recording and the ambient cues of the listening room, assuming that the recording contains them and that the listening space is at least somewhat reactive. With that in mind...

Strictly speaking, ANY ambient cue (omnidirectional or not) added by the listening room constitutes an inaccuracy, in the sense that it adds, subtracts, or alters information about the music as it is represented on the recording. But listening to a recording in a completely unreactive listening room (in effect, an anechoic chamber) would not be a rewarding musical experience, by any conceivable standard. Hence, it seems to me that virtually all audiophiles, myself included, are willing to tolerate a certain amount of inaccuracy for the sake of a more rewarding musical experience. The question then becomes: What are acoustical characteristics of those inaccuracies? In other words, some listening room inaccuracies are more musical than others, which seems to me to be a rather uncontroversial thing to say. I guess the point I am wandering around in search of is:

The goal of creating omnidirectional ambient cues at the listening position does, as you point out, result in inaccuracies. But ALL listening rooms result in inaccuracies. So we might as well try to design a room whose inaccuracies enhance the experience of listening to music, and for many audiophiles, that means enhancing the illusion that “you are there.”
In the course of this thread, I have suggested at least three possible approaches to constructing a listening room, each with distinct consequences for creating the illusion that "you are there." A listening room may be constructed so that it…

(1)…acoustically emulates a recording space.
(2)…accurately reproduces what is on the recording.
(3)…sounds interesting, as judged by the individual listener.

RE: Approach (1). A lot of the discussion has focused on the benefits and liabilities of approach (1) – constructing a listening space that acoustically emulates the recording space. I have acknowledged that, although it may be an effective way to create the illusion that “you are there,” it is not a practical approach to constructing a listening room. Its impracticality results from the fact that, to the extent that your listening room emulates a particular recording space, it will fail to emulate acoustically dissimilar recording spaces. Hence approach (1) makes your listening room “recording-specific,” which, for most audiophiles, is an unacceptable drawback of this approach.

RE: Approach (2). Constructing a listening space that accurately reproduces what is on the recording is the prevailing approach in the design of professional recording studios. Accuracy is achieved by making recording studios, to a large extent, acoustically unreactive. However, most audiophiles, myself included, seem to prefer a listening space that is considerably more acoustically reactive than a typical recording studio. The evidence for this belief can be found by looking at the virtual systems here on A’gon.

It could be argued that most audiophiles simply ignore the acoustical treatment of their listening rooms, and so their rooms tend to be acoustically reactive by default. Or that most audiophiles would rather put money into new equipment than a better room. Or that acoustical treatments rank low in WAF, which makes their use less likely. I think there’s a lot of truth to those observations. Nevertheless, I believe that audiophiles also prefer acoustically reactive rooms for more rational reasons (“rational” in the sense of ‘consistent with their goals’). Some of those reasons: Unreactive rooms require a large amount of amplification to reach realistic SPL’s. Unreactive rooms can result in poor speaker performance for many consumer speakers, which are designed to interact with the listened space and “voiced” by manufacturers in a reactive room. Unreactive rooms are often perceived as less “lifelike,” and hence less musically involving. I would add this list that unreactive rooms are less likely to create the illusion that “you are there,” though I recognize that this is a point of controversy. For these and other reasons, I think approach (2), while the conventional approach to recording studio design, is of somewhat limited value to the average audiophile.

RE: Approach (3). Constructing a listening space that sounds interesting, as judged by the individual listener, seems like a natural solution to the shortcomings of approach (2). But it has its own liabilities. To begin with, it potentially suffers from the same problem as approach (1), namely, it may result in a the listening room that is “recording-specific.” In addition, tastes change over time, both as a consequence of age and as a consequence of acquired expertise. In light of that, approach (3) may also suffer from being too “listener-specific.” Finally, approach (3) gives little or nothing in the way of specific guidance to the audiophile other than “do what sounds right.” That advice, while simple to understand, is not simple to implement, since it does not describe any smaller, instrumental goals that would make the advice actionable.

Thus all three approaches above leave a lot to be desired. I believe that there is a fourth approach - to try to construct a listening room that sounds different for each recording. On small recordings, it would sound small. On big recordings, it would sound big. Its characteristics would change as the recordings change. In other words, the approach is to try to construct a listening room that…

(4)…sounds paradoxical.

Yes, I know, I have gone far down the rabbit hole with this one. But if you will follow me a little further, you will see that I have not gone completely mad. What I am trying to express is the idea that the acoustical characteristics of some listening spaces are psychologically ambiguous. That is, some listening spaces sound like they have different physical features under different conditions. With some recordings, the listening space sounds like it has one set of physical features. With other recordings, it sounds like it has another set of physical features. So, from a psychoacoustic standpoint, the listening space is paradoxical. Hence the term ‘paradoxical listening room.’ I have a hypothesis about how a paradoxical listening room is created, namely by the combination of:

(i) neutrality
(ii) complexity

RE: (i). Neutrality. In using the term ‘neutral,’ I am violating my oath not to mention that word on this thread, lest it be perceived as a violation of a cease fire that was arrived at after months of painstaking negotiation. However, it is the right word for the discussion at this point, and so worth the risk.

To say that a listening room is ACOUSTICALLY NEUTRAL is to say that it has a LOW AMOUNT OF CONSTANT INACCURACIES. An inaccuracy is “constant” when it stays more or less the same under varying conditions. An example of a constant inaccuracy is a room mode, the frequency and relative amplitude of which stay more or less the same across different recordings. A constant inaccuracy is another way of saying a "coloration." As colorations are reduced, the listening room becomes more neutral. And as the listening room becomes more neutral, it has the potential to become more paradoxical, provided that it is also sufficiently complex. Which brings me to…

RE: (ii). Complexity. To say that a listening room is ACOUSTICALLY COMPLEX is to say that has a HIGH AMOUNT OF VARIABLE INACCURACIES. An inaccuracy is “variable” when it changes under varying conditions. An example of a variable inaccuracy is a randomly diffused reflection, the frequency and phase of which change significantly across different recordings. As variable inaccuracies are increased, the listening room becomes more acoustically complex. And as the listening room becomes more acoustically complex, it becomes more paradoxical, assuming it is sufficiently neutral.

So, my hypothesis is that, in combination, neutrality and complexity create a listening space that is paradoxical, in the sense that its acoustical characteristics are psychologically ambiguous. A listening space that is ambiguous approximates the benefits of one that acoustically emulates the recording space, without the liabilities of the latter approach, namely making the listening room “recording-specific.” So, for the audiophile who listens to a wide range of recordings with vastly different recording spaces, a paradoxical listening space is the closest he can come to having a different listening room for each type of recording. In light of this, constructing a paradoxical listening room may be the best way to consistently create the illusion that “you are there.”
Ultimately for me, the main point in all of this is that even your paradoxical listening room would greatly vary from audiophile to audiophile.

Learsfool – There may be a variety of ways to create a paradoxical listening room, but I suspect they would have a lot in common - for example, the liberal use of mathematically-derived diffusion. An extreme example of this approach is George Massenburg’s Blackbird Studio C. That recording space is perhaps the apotheosis of efforts to construct a paradoxical listening room. According to Massenburg:

The room is conducive to accurate work because we have taken away the boundary effect by “eliminating” the walls.

Blackbird Studio C is described elsewhere in the following way:

The experience of this room is that one is unaware of sound reflection from the walls: it sounds almost anechoic, yet it has reverberation.

Of course, no ordinary audiophile can construct such an ambitious listening space. But Blackbird Studio C seems to me to be an “existence proof” that a paradoxical listening room is possible. And its acoustical design approach could be implemented, on a more modest scale, by ordinary audiophiles like us.

For instance, if one switched out the speakers in such a room, this would have a much greater effect on the sound than switching out acoustic treatments while keeping the speakers the same. Or would you not agree?

No, I don’t agree. But that is probably another infinite staircase. :-)
One thing I will say is that Blackbird Studio C is designed to be a recording space, and most definitely NOT a listening space.

Learsfool - According to the Blackbird Studio website, Studio C is a space for "editing, overdubbing, and mixing." In other words, it is NOT identified as a recording space. Maybe by "recording space," you meant re-recording space, i.e. mixing space.

In any case, Studio C is not designed to be a room for recording performers and instruments with microphones. It is a room for editing and mixing those recordings after they have been captured elsewhere. As such, it is a listening space "par excellence." In my view, ALL editing and mixing rooms are listening spaces. That seems to me to be an uncontroversial statement. Maybe I am missing something.

As they say, it would be mostly quite dead, and any reverb heard in there would sound very strange indeed if you were actually physically present.

My understanding is that Studio C is NOT acoustically dead, and that that was the whole point of using massive amounts of diffusion and very little absorption.

It is definitely designed for multi-track recording of electronic instruments primarily.

Again, my understanding is different. According to the website, Studio C is described as being designed for BOTH stereo and multi-track mixing.

I have several thoughts I would like to share with you about some things in those articles, which I think would be better to send you in a private email, as they would be slightly off topic here - I will do this hopefully tomorrow, through the audiogon system, if you don't mind.

Of course. :-)
As horrifying as it is to audiophiles, the future of creating the illusion that "you are there" may be digital signal processing. Tgrisham posted a thread today about a Stereo Times article about 3D audio. That got me searching the web for related information. In five minutes, I turned up this:

...we try to produce the illusion in a listener of being in a "virtual" acoustic environment which is entirely different from that of the space in which he (or she) is actually located. We are thus attempting to achieve the long sought-after goal of making a listener in his living room hear sound as if he were in a concert hall.

The availability of modern electronic technology for processing acoustic signals digitally has transformed our ability to generate this illusion, almost irrespective of the environment (living room, office or automobile interior) which surrounds the listener. The approach that we take is to process acoustic signals prior to their transmission by loudspeakers. We undertake this processing in order to generate the illusion in the listener that sound is coming from a number of "virtual" sources in well defined spatial positions relative to the listener. Of course, the intention of conventional "stereo" sound reproduction by loudspeakers is to produce just such an illusion, but two channel stereophony is capable only of producing acoustic virtual source images over a very narrow range of spatial positions, these being restricted to positions in the plane of, and in between, the two loudspeakers used for reproduction. The use of modern signal processing techniques can remove this restriction, even when only two loudspeakers are used for reproduction.

A number of approaches to "3D Audio" have been developed in recent years, but few have correctly tackled the basic signal processing problem that has to be solved. This is the design of a processing scheme that ensures that the correct signals are produced at the listener's ears. In order to achieve such a goal, the processing scheme has to account for the effect on the signal of the loudspeakers, of the transmission path (including room reflections), and of the effect of the listeners head and torso on the propagation of sound to the ears. The central problem to be tackled is one of "inversion" where all these effects have to be "turned upside down" (and thus compensated for) before the signals are transmitted by the loudspeakers. This is a problem with many technical subtleties, but by tackling it correctly, it's solution can produce remarkable results.

That is from University of Southampton's Institute of Sound and Vibration Research.

Soon we will be able to forget all about listening rooms, paradoxical or otherwise. :-o
A recent thread discusses a Stereo Times interview with Duke LeJeune of AudioKinesis. A passage in the interview struck me as relevant to an idea I've been trying to advance on this thread, namely that omnidirectional ambient cues are necessary for creating the illusion that "you are there." In the interview, Duke says:

We are accustomed to thinking of reflections as causing coloration and degrading clarity, and philosophically we don’t like the room adding to the recording something that was not originally there. But if the reverberant field is done right (which is something we can come back to), timbre is more natural and clarity is actually improved! That’s right, controlled tests have shown that speech intelligibility is improved by normal in-room reflections. Apparently the ear is better able to decipher complex sounds when it gets multiple “looks” in the form of reflections. The direction that reflections arrive from plays a role as well. Reflections that arrive from the same direction as the direct sound are more likely to be perceived as coloration than are reflections that arrive from the sides. And, reflections that arrive from the sides are more effective at imparting a sense of spaciousness and envelopment. One benefit of my recommended 45-degree toe-in is that it ensures a relatively large proportion of the reverberant energy will be arriving from the sides. The ear derives tonal balance from a weighted average of the incoming sounds, so the reverberant energy plays a significant role there. When the spectral balance of the reflections is very close to that of the first-arrival sound, perceived timbre is richer and more vivid. This is why we listen to grand pianos and choral groups in lively recital halls rather than in thickly-padded rooms. In my opinion the goal of high-end audio is to recreate, as closely as is practical, the perception of listening to live music.

Interesting thoughts on the role of reverberant sound in creating what Duke calls "the perception of listening to live music," which seems to be another way of saying the perception that "you are there."