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

Bryon and Al, you both make some very interesting points! In general, I agree with most all of them, particularly Al's. Regarding this bi-directional vs. omni-directional subject, though, I do think it is very important to remember that in a good concert hall, sound is really not coming from EVERY direction at exactly the same moment. Acousticians try to design the overall space so that as much of the sound as possible goes directly to the audience, and that the reflected sound is channeled in such a way that it interferes with this as little as possible. So although sound does come from many different directions, it does not come from all of them anywhere near equally, and the overall effect is not PRIMARILY omni-directional, only secondarily so. Again, this is assuming a well-designed hall, and I am admittedly over-simplifying. I think the point I am trying to make here is similar to Al's point no. 3 he asked you to reconsider. (On a side note, this is why some musicians I know claim that even stereo reproduction sounds fake, and do as much of their listening as possible to older mono recordings! I don't go that far myself, but I have been exposed to a truly great mono set-up, and had to admit that it was at least as realistic as the best stereo set-ups I have heard.)

This point leads to another - 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, as I believe you put it, in these cases, and this is why I believe you are overestimating it's importance. It must be a very good listening space indeed, beyond the capabilities of the vast majority of us, to come close to recreating the sound of a concert hall in their listening room. I am not suggesting the room is unimportant (it can definitely help in the ways you suggest), but merely not as important as the speakers, and certainly not as important as the recording itself, which is by far the greatest factor.

Another point I would make, per our discussion of speaker types, is that while I think I understand your comment that "neither [speaker type] is inherently superior to the other, when considered independent of the listening room," in practice, one cannot listen to the speaker independent of the listening room, so while that statement may be true in theory, it doesn't have any practical value.

As for the binaural recording issue, I have absolutely no experience with this - I have never heard a binaural recording. The subject is interesting, and I would like to hear one sometime, but until then I will remain skeptical, for the reasons I already stated. And I still remain convinced that though the very best types of headphones out there may be able to provide some ambient cues, they will not be of anywhere near the quality of normal speakers. I do not claim to know the scientific reasons behind it, but it has much to do with what Al alluded to about the ears not picking up the sound in the same way. I read a very good article about this subject a few years ago written by an engineer, but have no recollection of where, unfortunately. I may try a Google search, and if I can find it, I will share the link.

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 Bryon. Yes, you interpreted my point no. 3 as I intended it, that the inclusion of what was direct sound in the recording space in an omnidirectional listening space presentation represents a significant inaccuracy, which must be traded off against the benefits of the omnidirectional listening space presentation.

The reason you didn't see no. 3 previously is simple -- it wasn't there when you started composing your previous response :-). As I mentioned in my subsequent post, I added it in sometime after initially submitting the post to which it was added, and by that time you were obviously working on your response (as shown by the fact that you referred to the headphone part of my post as item 3, rather than item 4 which it subsequently became).

I suppose that the bottom line in the tradeoff we are referring to comes down to matters of degree, which in turn are dependent on the speakers, the constraints imposed by the particular listening space, the types of recordings that are listened to, and the preferences of the listener.

The only exception I would take with respect to your last post would be the statement that:

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.

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. Although of course they can be extremely revealing and analytical. And once again a tradeoff is involved, because their accuracy (in the sense that you are using the term here) is aided by the absence of room effects.

Best regards,
-- Al

Hello all, another interesting thread from Bryon. As a sidebar, after years of casual listening to quite decent Sennheiser HE60 electrostatics through the stock head amp, I recently had an opportunity to hear an all-out custom tube head amp driving current top-model Sennheiser dynamic headphones. For the first time I think I "got it" regarding what headphones can achieve in terms of disintermediating electronics and room affects from the music. The key insight was that I had never heard a headphone set-up that approached my regular stereo in quality. Most audiophiles outside of the "head-case" niche are likely in the same boat. IME the gain in detail and separation out-weighed the loss of natural acoustic space.

On a lark I set about modifying my Headroom line-level processor to the point where I felt that the advantage of the crossfeed process was not off-set by degradations in the electronics that had relegated this unit to storage for some years. Briefly, crossfeed has the effect of shifting forward and tightening images that in normal listening appear furthest to the side and rear. Only images that are way out to the side and rear seem affected. The effect is to make a headphone "sound stage" analogous to the experience of a conventional listening room. So I am inclined to agree with Al, that this more forward sound stage is natural, with the caveat that a process like crossfeed can spook the ear into hearing a natural sense of the room acoustic, while preserving the advantage that headphones have in being unfettered by reflected sound. As with so much in hi-fi, its all about the implementation.

Bryon, regarding your recent post on ambience cues, directionality and listening rooms, I think you may be overlooking some aspects of what is going on with respect to the cues in the recording versus the cues from the listening room.

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, but it illustrates some issues:

1) Consider a single drum hit. From the optimal listening position, the stereo effect tells you that there is a drum set on the stage, left of center. What does the wall directly to the right of the speakers see? It sees two sources (the left and right speakers), separated in time by the distance between the speakers. The reflections along the wall will see a delay between the two sources that varies something like the sine of the takeoff angle. The same for the left wall, other objects in the room, etc. This effect does not exist in the original performance. These echoes come to your ears as something other than what the single source on the recording produced. Let’s call it “source distortion.”

2) Now let’s replace the pair of speakers with a single speaker in the position of the drum set. The drum hit now behaves as a single source: the direct wave travels from the speaker to the listener as it should, and then hits (say) the back wall and comes back to the listener at exactly the same time as the echo in the recording gets to the listener as a direct wave. Thus, you have achieved your goal of reinforcing the primary cue. But the recorded echo itself then travels to the rear wall and comes back to the listener as a secondary echo that did not exist in the original performance. Let’s call this “echo distortion.”

3) Of course, your room is not exactly the configuration of the recording room, so on top of #1 and #2, you hear your primary room echo and the echo on the recording at different times. Let’s call this “temporal distortion.”

In general, to get ambience cues on the recording to be omnidirectional in your listening space, you would have a) primary echoes from your listening room that were stronger than the secondary recorded echoes, and thus dominant, b) recorded ambience cues reflected by your room that arrived at your ears too late (i.e., the reflected ambience cues will be out of sync with the directly radiated (from the speakers) ambience cues), and c) many of the reflections suffering from source distortion.

I see this as a continuum. If you succeed in recreating a recording space perfectly, you get source and echo distortion with it. If your space is some average of the spaces you prefer (say, a generic jazz club), or you listen to recordings recorded in more than one place, you’ll also get temporal distortion. If you manage to suppress echo and temporal distortion (or the recording has weak ambience cues), then the direct echoes from your room will dominate, and you’ll actually get a “they are here” effect, rather than the desired “you are there” effect. If you suppress your room so that the recorded cues dominate, you get “you are there” cues but they’ll be bidirectional (but only if the recording has sufficient cues -- if it doesn’t you may get a somewhat dead or recording studio sound).

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), and it doesn’t seem possible to get time/phase correct omnidirectional ambience cues that aren’t dominated by your room, rather than the recording (short of electronic intervention, which you and Learsfool have said is not desirable).

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.

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)

All of this comes with the caveat that what I say may be true for certain kinds of cues and not others.