Blue or red pill?

[adamdea]

Here is a nice short lecture dealing with the importance of the ventriloquism after effect in terms of the way it helps us to calibrate space and resolve ambiguous information

https://www.coursera.org/learn/human-brain/lecture/GLCyM/lecture-4-6-s-e-ventriloquism-and-finding-sounds

This is really important because it shows that the way we localise sound is based on a perceptual model built up over time. Now consider how this might affect our ability to locate sound based on auditory information only when we can't see the sound source or the room. 

What does this tell us about localisation in term of cues a) in the recording/sound I am currently hearing and b) not in the recording?

[sandyk]

40 minutes ago, adamdea said:

What does this tell us about localisation in term of cues a) in the recording/sound I am currently hearing and b) not in the recording?

 

 Can you prove that those Cues are not embedded in the recording due to phase differences ?

[gmgraves]

19 hours ago, mansr said:

I'm not disagreeing. What I objected to was the idea that there would be somehow be a cancellation of some frequencies.

There might be some cancellation of ultra-sonic frequencies, but it's irrelevant. 

[gmgraves]

3 hours ago, mansr said:

A stereo recording unambiguously captures the direction of a sound source. Depth is not captured whatsoever. When we perceive a reproduced sound as distance, it is because this fits our mental model of the world, not in any way because the recording actually contains depth information. Why do you persistently refuse either understand or accept this distinction?

My experience as well as that of Alan Blumlein in the 1930's; as well as people like John Eargle, Bert Whyte, and J. Gordon Holt more recently, tell a different story. Whether illusory or not. The phase cues that locate instruments nearer or farther away from a stereo pair and at (near) stage level or higher are generated by an ensemble playing live in an actual space. When we use true stereo miking techniques to mike the space that these instruments inhabit while playing rather than the instruments themselves, all the cues that humans use to locate sounds: right and left direction, whether the sources are nearer or farther away, whether they emanate from eye level or above eye level or below eye level, and whether they are coming from behind us are all in the sound field being generated by that musical ensemble and are reinforced by the acoustics of that space. If we place a stereo pair of microphones in that sound field, depending on how the microphones are made, what their characteristics are, and where in the sound field that they are placed, they are going to capture whatever part of that sound field that they are capable of capturing. A stereo pair of cardioids, for instance, aimed at an ensemble on the stage of an auditorium, will not pick-up much hall ambience from behind them because the mikes are designed to not have much sensitivity to sounds coming from directions that are severely off-axis to the mike's polar pattern. But, from the direction at which they are aimed, these mikes will pick-up all the directional, loudness and phase cues being generated by the musical ensemble being captured. These are the same cues that tell us human listeners that a sound is coming from the left or the right of us, whether that sound is nearer or farther away, and whether, like the squeak of a mouse, it comes from somewhere on the floor beneath us, or like the caw of a hawk flying in the sky above us, it makes us look up at the source of that caw! That sound field can be captured simply by using the right microphones in the correct stereo manner. 

[STC]

4 hours ago, mansr said:

When we perceive a reproduced sound as distance, it is because this fits our mental model of the world, not in any way because the recording actually contains depth information.

 

Depth cues are recorded. Maybe, you are right that depth as an unique value itself not encoded in the recordings but we perceive depth or distance by other cues such as loss of HF and reverbs. These cues are all recorded.  

[Audiophile Neuroscience]

4 hours ago, mansr said:

 

 

A stereo recording unambiguously captures the direction of a sound source. Depth is not captured whatsoever.

 

A stereo recording unambiguously captures the *physical cues* that when played back are the cues we use to perceive as direction.It also unambiguously captures the physical cues that when played back we perceive as depth. These are objective truths based on evidence. You are incorrect to imply otherwise.

 

4 hours ago, mansr said:

 

When we perceive a reproduced sound as distance, it is because this fits our mental model of the world, not in any way because the recording actually contains depth information.

 

In both cases the distance and depth perception are illusions. It is impossible not to have the physical stimuli present in one of either the recording or audio signal (or both). the mechanism of the perceptual experience is irrelevant, fitting models or anything else is irrelevant. Cues are there that excite a perception.

 

4 hours ago, mansr said:

Why do you persistently refuse either understand or accept this distinction?

 

because i am approaching this from a purely objectivist viewpoint, and have evidence.I cannot help it if you remain subjective and ignore evidence.

 

4 hours ago, mansr said:

How obtuse is it possible to be? beerandmusic is a little worse, but you're getting pretty close.

 

Insulting Beery simply reflects more on your untenable position.

 

I do get that it is threatening for you to consider there has to be physical factors conveyed in the signal that you may not or cannot measure. Your subjective views appear immovable at this point so little point arguing further. 

 

Lets wait and see what happens at Mani's. Understandably any claims by you that objective measurements have failed to identify correlates of audible differences cannot be taken seriously,IMO.

 

Like I said before have fun on the day, measurements or no

 

[mansr]

1 hour ago, gmgraves said:

My experience as well as that of Alan Blumlein in the 1930's; as well as people like John Eargle, Bert Whyte, and J. Gordon Holt more recently, tell a different story. Whether illusory or not. The phase cues that locate instruments nearer or farther away from a stereo pair and at (near) stage level or higher are generated by an ensemble playing live in an actual space. When we use true stereo miking techniques to mike the space that these instruments inhabit while playing rather than the instruments themselves, all the cues that humans use to locate sounds: right and left direction, whether the sources are nearer or farther away, whether they emanate from eye level or above eye level or below eye level, and whether they are coming from behind us are all in the sound field being generated by that musical ensemble and are reinforced by the acoustics of that space. If we place a stereo pair of microphones in that sound field, depending on how the microphones are made, what their characteristics are, and where in the sound field that they are placed, they are going to capture whatever part of that sound field that they are capable of capturing. A stereo pair of cardioids, for instance, aimed at an ensemble on the stage of an auditorium, will not pick-up much hall ambience from behind them because the mikes are designed to not have much sensitivity to sounds coming from directions that are severely off-axis to the mike's polar pattern. But, from the direction at which they are aimed, these mikes will pick-up all the directional, loudness and phase cues being generated by the musical ensemble being captured. These are the same cues that tell us human listeners that a sound is coming from the left or the right of us, whether that sound is nearer or farther away, and whether, like the squeak of a mouse, it comes from somewhere on the floor beneath us, or like the caw of a hawk flying in the sky above us, it makes us look up at the source of that caw! That sound field can be captured simply by using the right microphones in the correct stereo manner. 

Are you seriously trying to claim that a pair of microphones can record the HRTF of a person who isn't even in the room?

[mansr]

2 minutes ago, Audiophile Neuroscience said:

I do get that it is threatening for you

I see you have run out of arguments.

[Sonicularity]

3 hours ago, acg said:

 

Atmospheric refraction perfectly explains this.  And I have measured it, more than once during my university degree, of both the sun and the moon.  They both move quite quickly and are relatively difficult to manually track through an instrument.

 

I don't want to disrupt this thread, but I'll just suggest that you do a little more research. What you claim does not make sense.  The moon size would actually measure smaller, not larger, due to atmospheric refraction.  There are numerous links available that can be found on this topic, and all come to the same conclusion.

 

https://cseligman.com/text/sky/atmosphericrefraction.htm

 

 

[Audiophile Neuroscience]

5 hours ago, adamdea said:

I'm not going to waste time going over digressions. This bit is the key to the impasse you are having with mansr and there is an easy way out of it if you think about it.

Consider the example of the (potential) relative depth cue by relative amplitude. Mansr's point is that because this information is wholly ambiguous (the two sounds sources might be at the same distance or..) you can't measure using only the data and different people will interpret that data differently for reasons which you apparently understand. So you can't measure the depth cues as such. It's  a category error. What would the units of this measurement be. 

That isn't the same as saying that once you had identified what property caused this perception in this person you could then in principle measure that property. But it would have to be specific to the application of this recording to this person. There isn't a special code for 2ft back and slightly to the left.

 

Nicely argued but in a sense, that you may have difficulty ( i dont accept you cannot at this point) measuring the cues, paraphrasing Mans, its not my problem. Without doubt the cues are there, without doubt they are perceived.That is the evidence. I do not contest for a minute that not all perceivers will perceive depth to same level or as consistently as for lateral distance. That does not invalidate that scientifically a (large) group can and do.

[mansr]

3 minutes ago, Sonicularity said:

I don't want to disrupt this thread, but I'll just suggest that you do a little more research. What you claim does not make sense.  The moon size would actually measure smaller, not larger, due to atmospheric refraction.  There are numerous links available that can be found on this topic, and all come to the same conclusion.

 

https://cseligman.com/text/sky/atmosphericrefraction.htm

If refraction occurred to any notable extent, the moon would appear compressed vertically when just above the horizon. It doesn't. End of story.

[Audiophile Neuroscience]

3 hours ago, adamdea said:

I did say that I wasn't going to pursue digressions but as long as it is understood that I have conceded that I was somehwat over -egging the pudding by saying that vision was the main source of sound localisation and only really saying that it is part of our everyday localisation (and that it tends to dominate actual auditory information in the case of conflict) then the main sources are listed here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2674475/.

"Although sound sources can obviously be localized on the basis of auditory cues alone, localization accuracy improves if the target is also visible to the subject (Shelton & Searle 1980; Stein et al. 1989). This is an example of a more general phenomenon by which the central nervous system can combine inputs across the senses to enhance the detection, localization and discrimination of stimuli and speed up reactions to them

...Conflicting visual cues can also influence the perceived location of a sound source. Thus, the presentation of synchronous but spatially disparate visual and auditory targets tends to result in mislocalization of the auditory stimulus, which is perceived to originate from near the location of the visual stimulus (Bertelson & Radeau 1981). 

....Nevertheless, visual localization is normally more accurate than sound localization and therefore tends to dominate conflicts between the two modalities, thereby enabling, at least within certain limits, spatially misaligned cues to be perceived as if they originate from the same object or event. Repeated presentation of consistently misaligned cues results in a shift in the perception of auditory space that can last for tens of minutes once the visual stimulus is removed (figure 2). This is known as the ventriloquism after-effect and has been observed in both human (Radeau & Bertelson 1974; Recanzone 1998; Lewald 2002) and non-human (Woods & Recanzone 2004) primates. 

Again presumably you know all of this. It at the very least supports the conclusion that the everyday functioning of a normal person's experience of sound location is going to involve their vision (and quite a lot else besides).  

 

Even ignoring visual input to "hearing" It still seems to me to be obvious that the absence of the spectral cues arising from the hrtf (let alone the ability to cross check by tilting and moving ones head) severely limits the ability to encode and decode sounds to and from ordinary stereo recording as well as explaining how our perceptual system may make certain guesses based on spectral information. 

 

Thanks Adam(?)

I will take a look. I applaud that you took the time to find evidence.

[fas42]

13 minutes ago, Audiophile Neuroscience said:

 

Nicely argued but in a sense, that you may have difficulty ( i dont accept you cannot at this point) measuring the cues, paraphrasing Mans, its not my problem. Without doubt the cues are there, without doubt they are perceived.That is the evidence. I do not contest for a minute that not all perceivers will perceive depth to same level or as consistently as for lateral distance. That does not invalidate that scientifically a (large) group can and do.

 

I'm curious whether you have had any listeners to a system which presented excellent depth, who didn't "get it", IOW, the illusion just completely failed to materialise for them, the cues did not register sufficiently to excite an impression of distance.

[Audiophile Neuroscience]

14 minutes ago, mansr said:

I see you have run out of arguments.

 

Only because you insist on remaining subjective and ignore objective reasoning supported by evidence. I cannot reason you out of a position you unreasonably hold.

[Audiophile Neuroscience]

2 minutes ago, fas42 said:

 

I'm curious whether you have had any listeners to a system which presented excellent depth, who didn't "get it", IOW, the illusion just completely failed to materialise for them, the cues did not register sufficiently to excite an impression of distance.

 

As stated earlier it is variable, even perceiving the phantom central image. However in my current system in past year so the answer is all people have perceived depth.

[mansr]

8 minutes ago, Audiophile Neuroscience said:

Only because you insist on remaining subjective and ignore objective reasoning supported by evidence. I cannot reason you out of a position you unreasonably hold.

You owe me a new irony meter. Mine exploded when I read that.

[sandyk]

44 minutes ago, mansr said:

I see you have run out of arguments.

 

 Why do you also keep ignoring the reports by George, who is also well qualified, and actually makes Classical Music recordings for others ?

[semente]

2 hours ago, gmgraves said:

My experience as well as that of Alan Blumlein in the 1930's; as well as people like John Eargle, Bert Whyte, and J. Gordon Holt more recently, tell a different story. Whether illusory or not. The phase cues that locate instruments nearer or farther away from a stereo pair and at (near) stage level or higher are generated by an ensemble playing live in an actual space. When we use true stereo miking techniques to mike the space that these instruments inhabit while playing rather than the instruments themselves, all the cues that humans use to locate sounds: right and left direction, whether the sources are nearer or farther away, whether they emanate from eye level or above eye level or below eye level, and whether they are coming from behind us are all in the sound field being generated by that musical ensemble and are reinforced by the acoustics of that space. If we place a stereo pair of microphones in that sound field, depending on how the microphones are made, what their characteristics are, and where in the sound field that they are placed, they are going to capture whatever part of that sound field that they are capable of capturing. A stereo pair of cardioids, for instance, aimed at an ensemble on the stage of an auditorium, will not pick-up much hall ambience from behind them because the mikes are designed to not have much sensitivity to sounds coming from directions that are severely off-axis to the mike's polar pattern. But, from the direction at which they are aimed, these mikes will pick-up all the directional, loudness and phase cues being generated by the musical ensemble being captured. These are the same cues that tell us human listeners that a sound is coming from the left or the right of us, whether that sound is nearer or farther away, and whether, like the squeak of a mouse, it comes from somewhere on the floor beneath us, or like the caw of a hawk flying in the sky above us, it makes us look up at the source of that caw! That sound field can be captured simply by using the right microphones in the correct stereo manner. 

 

What do you think would happen if the mics in the following video were pointing forward instead of downwards at the piano?

Would it sound like the piano was 10 feet below the speakers?

 

 

[Audiophile Neuroscience]

4 minutes ago, mansr said:

You owe me a new irony meter. Mine exploded when I read that.

Thought you'd like it . maybe your irony meter is just broken like the meters used to measure physical cues.

[fas42]

2 hours ago, gmgraves said:

When we use true stereo miking techniques to mike the space that these instruments inhabit while playing rather than the instruments themselves, all the cues that humans use to locate sounds: right and left direction, whether the sources are nearer or farther away, whether they emanate from eye level or above eye level or below eye level, and whether they are coming from behind us are all in the sound field being generated by that musical ensemble and are reinforced by the acoustics of that space. If we place a stereo pair of microphones in that sound field, depending on how the microphones are made, what their characteristics are, and where in the sound field that they are placed, they are going to capture whatever part of that sound field that they are capable of capturing. A stereo pair of cardioids, for instance, aimed at an ensemble on the stage of an auditorium, will not pick-up much hall ambience from behind them because the mikes are designed to not have much sensitivity to sounds coming from directions that are severely off-axis to the mike's polar pattern. But, from the direction at which they are aimed, these mikes will pick-up all the directional, loudness and phase cues being generated by the musical ensemble being captured. These are the same cues that tell us human listeners that a sound is coming from the left or the right of us, whether that sound is nearer or farther away, and whether, like the squeak of a mouse, it comes from somewhere on the floor beneath us, or like the caw of a hawk flying in the sky above us, it makes us look up at the source of that caw! That sound field can be captured simply by using the right microphones in the correct stereo manner. 

 

The position I come from is simply an extrapolation of this: whether the intention was to capture this information or not, and whether the cues are partially or completely manufactured on the mixing desk makes no difference - a sense of space and depth can be experienced in all recordings, unless they went to extreme lengths to explicitly prevent this! The better the playback, the more "powerful", convincing is the sense of this - the perceived space may not be a single one; it can be multiple spaces, of different sizes, overlaid upon each other - as would intuitively be the case, the more the mix is manipulated the more the spaces seem separate, distinct from each other - but still with full integrity; each retains its indivduality.

 

The advantage of aiming for the highest level of SQ is that all the recordings that one has can "unfold" in this manner - increasing the pleasure and satisfaction in the listening.

[esldude]

3 hours ago, mansr said:

OK, I see what you're getting at. How does this compare to all the other comb filtering that is anyway present, in both the recording and playback venues? Did you take into account that the ears are not equidistant from the speakers and that they do not receive the same intensity from both?

My initial look was combining the two channels to see if the comb filtering was present.  Of course if I estimate one channel is -6 db vs the other in each ear, and that the result is opposite polarity in each ear relative to the other then I am not sure what our brain would make of it.  And the size of the comb filter effect is reduced.  

 

In listening, I listened over two channels to the two channel recording.  I listened to a track where I combined into mono the two channels and played it over two speakers.  I listened to the combined track over one speaker.  I then did the same with one channel inverted vs the other for the two channel version.  (one summed channel would cancel to nothing if one is inverted).   None gave any impression of height.  All sounded like indistinct mono in the center just about in line with the replay speakers with two speakers in use.  Sounded pasted to the speaker in one channel use.  

[Audiophile Neuroscience]

4 hours ago, adamdea said:

I did say that I wasn't going to pursue digressions but as long as it is understood that I have conceded that I was somehwat over -egging the pudding by saying that vision was the main source of sound localisation and only really saying that it is part of our everyday localisation (and that it tends to dominate actual auditory information in the case of conflict) then the main sources are listed here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2674475/.

"Although sound sources can obviously be localized on the basis of auditory cues alone, localization accuracy improves if the target is also visible to the subject (Shelton & Searle 1980; Stein et al. 1989). This is an example of a more general phenomenon by which the central nervous system can combine inputs across the senses to enhance the detection, localization and discrimination of stimuli and speed up reactions to them

...Conflicting visual cues can also influence the perceived location of a sound source. Thus, the presentation of synchronous but spatially disparate visual and auditory targets tends to result in mislocalization of the auditory stimulus, which is perceived to originate from near the location of the visual stimulus (Bertelson & Radeau 1981). 

....Nevertheless, visual localization is normally more accurate than sound localization and therefore tends to dominate conflicts between the two modalities, thereby enabling, at least within certain limits, spatially misaligned cues to be perceived as if they originate from the same object or event. Repeated presentation of consistently misaligned cues results in a shift in the perception of auditory space that can last for tens of minutes once the visual stimulus is removed (figure 2). This is known as the ventriloquism after-effect and has been observed in both human (Radeau & Bertelson 1974; Recanzone 1998; Lewald 2002) and non-human (Woods & Recanzone 2004) primates. 

Again presumably you know all of this. It at the very least supports the conclusion that the everyday functioning of a normal person's experience of sound location is going to involve their vision (and quite a lot else besides).  

 

Even ignoring visual input to "hearing" It still seems to me to be obvious that the absence of the spectral cues arising from the hrtf (let alone the ability to cross check by tilting and moving ones head) severely limits the ability to encode and decode sounds to and from ordinary stereo recording as well as explaining how our perceptual system may make certain guesses based on spectral information. 

 

Not sure what's going on in my browser but all links open to the same reference, Visual influences on auditory spatial learning. A quick read but agree mostly.

[fas42]

18 minutes ago, semente said:

 

What do you think would happen if the mics in the following video were pointing forward instead of downwards at the piano?

Would it sound like the piano was 10 feet below the speakers?

 

 

I would say, think how your ear/brain would hear the sound if your head were in the middle of where those mics were - and you then adjusted your head, to look at different points in the room, noting how the sound came across in each position.

[semente]

3 minutes ago, fas42 said:

 

I would say, think how your ear/brain would hear the sound if your head were in the middle of where those mics were - and you then adjusted your head, to look at different points in the room, noting how the sound came across in each position.

 

You say that because I've shown you the video.

 

What I think would happen is that a system would reproduce the piano between the speakers with perhaps a bit of high frequency roll-off.

[Ralf11]

12 hours ago, mansr said:

If you measure the angle occupied by the moon when near the horizon and again when high in the sky, you get almost exactly the same value. Nevertheless, the rising or setting moon is often perceived as twice the size of the moon when (more or less) overhead. Atmospheric refraction can't explain this.

 

my understanding is that no one has yet fully explained the perceptual size inflation...