Sanity Check

[STC]

34 minutes ago, mansr said:

The recording conveys only a small amount of the spatial information we are able to pick up in person. This is not because our ears are in any way superior. It is merely because two speakers can never recreate the full sound field of the original event.

 

Precisely, the recording minimize the spatial information. The microphone is capable of picking up more than what human ears could. The problem is reproducing them from the same direction, i.e., from the main front speakers. The soundfield is a 360 degree event. Direct sound plus reflection and reverberatio and some rear delay. 

 

The spaciousness feeling is due to reflection and lateral reverberation arriving from the side. The keyword is FROM THE SIDE. This already established years ago. 

 

One recent quote....

 

“Prior to about year 2000 most researchers reported that the most important component of listener envelopment is the late energy arriving at a person’s ears from lateral directions. Recently, Furuya, Fujimoto, Wakuda and Nakano[3] found from extensive subjective measurements of listener envelopment LEV that late vertical energy and late energy from behind, respectively, affect LEV by approximately 40 and 60 percent of late lateral energy. Soulodre et al’s study found that total late energy is a better component of LEV than late lateral energy. Because late lateral energy values have not been published for most concert halls and because there is conflicting evidence as to which is better, total late energy is used in this paper.”

 

“The terms “spatial impression” and “early lateral reflections” are ensconced in the terminology used to describe the acoustics of concert halls. In the late 1960s, through listening experience and research, Harold Marshall discovered that early reflections arriving from lateral directions created a desirable sense of spaciousness (1). This phenomenon, which he originally called “spatial responsiveness” (later, spatial impression), was then extensively investigated by Michael Barron in his PhD thesis. Later, Barron and Marshall derived the “early lateral energy fraction” (LF) as a linear measure of spatial impression (2). Recent research by Pätynen et al. (3) has also established that the perceived dynamic range is enhanced when the room geometry provides strong lateral reflections. LF has become one of the most important acoustic descriptors that correlates highly with subjective listener preference for concert hall sound. Today the term spatial impression refers to two subjective effects: apparent source width, and listener envelopment. The first corresponds to Marshall and Barron’s work, while listener envelopment is related to the level of the late lateral sound energy (4).

LF is defined as the linear ratio of the lateral early energy to the total early energy. Barron and Marshall found, through subjective listening tests with a simulation system, that the degree of spatial impression was maximised when the sound arrived side on to the listener and zero when the sound arrived from the direction of the source. The test results showed a correlation with cos ( ), where   was the angle between the lateral reflection and the axis through the ears. LF is generally measured from impulse responses obtained using a cosine or “figure-of-8” microphone (to measure the lateral energy) in conjunction with an omnidirectional microphone (to measure the total energy) (5).”

 

End of quote. 

 

 

 There are also binaural recording made using dummy head at the listeners location. These recordings captures everything that we hear and the it contains all the direct and reverberation sound. The difference why this recording works better to give the spatial information than ordinary stereo is because the direction of reverberation comes from side and the opposite reverberation does not get mixed to the other  ear.  The brain is still the same and still process the same sound between live and recorded. 

 

[fas42]

37 minutes ago, mansr said:

The recording conveys only a small amount of the spatial information we are able to pick up in person. This is not because our ears are in any way superior. It is merely because two speakers can never recreate the full sound field of the original event.

 

And what is the evidence that such is the case? Is the assumption there that the human hearing system is too limited in its capabilities, to be able to recreate a reasonable similarity to the original event as an internal 'picture', with the clues derived from audio playback?

[semente]

3 minutes ago, STC said:

 

Precisely, the recording minimize the spatial information. The microphone is capable of picking up more than what human ears could. The problem is reproducing them from the same direction, i.e., from the main front speakers. The soundfield is a 360 degree event. Direct sound plus reflection and reverberatio and some rear delay. 

 

The spaciousness feeling is due to reflection and lateral reverberation arriving from the side. The keyword is FROM THE SIDE. This already established years ago. 

 

To reproduce the original soundfield you'd need to be surrounded by loudspeakers. This would not be enough:

 

 

And you'd need a sphere with as many microphones to capture it.

 

Of course we'd have to deal with comb filtering and dispersion interference that would probably be massive with so many sound sources and the room would have to be semi-anechoic.

 

Listening to 2 channel stereo requires a certain degree of abstraction but not more than looking at a photograph or watching TV. I don't need 3D to enjoy a film or a documentary, in fact my experiences with 3D video were quite negative: the 3D-ness detracted from the realism and other, to me more important, aspects of image quality were negatively affected.

For me, music is sound, accurate spatial reproduction is a secondary, almost superfluous, effect.

[mansr]

19 minutes ago, STC said:

There are also binaural recording made using dummy head at the listeners location. These recordings captures everything that we hear and the it contains all the direct and reverberation sound. The difference why this recording works better to give the spatial information than ordinary stereo is because the direction of reverberation comes from side and the opposite reverberation does not get mixed to the other  ear.  The brain is still the same and still process the same sound between live and recorded. 

Binaural can work very well, but it still fails to recreate the perceptual cues derived from head movements. It also fails to account for individual differences and asymmetries in head and ear shape.

[mansr]

16 minutes ago, fas42 said:

And what is the evidence that such is the case? Is the assumption there that the human hearing system is too limited in its capabilities, to be able to recreate a reasonable similarity to the original event as an internal 'picture', with the clues derived from audio playback?

It's simple physics. The clues you speak of are just not there.

[fas42]

5 minutes ago, semente said:

Listening to 2 channel stereo requires a certain degree of abstraction but not more than looking at a photograph or watching TV. I don't need 3D to enjoy a film or a documentary, in fact my experiences with 3D video were quite negative: the 3D-ness detracted from the realism and other, to me more important, aspects of image quality were negatively affected.

For me, music is sound, accurate spatial reproduction is a secondary, almost superfluous, effect.

 

The comparison with video is relevant, because it was determined some time ago that very high quality visual replay actually could throw an internal processing switch - the mind/body accepts that what it is looking at is real, and the person can't stop themselves reacting to the situation as a real world scenario that they are involved in - for example, the film shows the viewer being in a car out of control careering down a hill - an audience member could literally suffer a heart attack ...

 

I've found that this happens with sound projection - the illusion is accepted; and spatial perspectives come as part of the package, automatically.

[fas42]

4 minutes ago, mansr said:

It's simple physics. The clues you speak of are just not there.

 

How can you be sure the clues aren't there?

[mansr]

Just now, fas42 said:

How can you be sure the clues aren't there?

Because they weren't recorded.

[STC]

5 minutes ago, mansr said:

Binaural can work very well, but it still fails to recreate the perceptual cues derived from head movements. It also fails to account for individual differences and asymmetries in head and ear shape.

 

All recording made to one individual’s preference.

 

Binaural works better in providing the spatial cues than a stereo. I did mention about head movements and headtracking headphones a couple of post ago. 

[fas42]

2 minutes ago, mansr said:

Because they weren't recorded.

 

IME the clues are recorded - but less than stellar playback conceals, blurs the critical information. Where is the evidence that the information is not actually present, as you claim?

[mansr]

1 minute ago, fas42 said:

IME the clues are recorded

Please explain how.

[STC]

17 minutes ago, semente said:

 

To reproduce the original soundfield you'd need to be surrounded by loudspeakers. This would not be enough:

 

 

And you'd need a sphere with as many microphones to capture it.

 

Of course we'd have to deal with comb filtering and dispersion interference that would probably be massive with so many sound sources and the room would have to be semi-anechoic.

 

Listening to 2 channel stereo requires a certain degree of abstraction but not more than looking at a photograph or watching TV. I don't need 3D to enjoy a film or a documentary, in fact my experiences with 3D video were quite negative: the 3D-ness detracted from the realism and other, to me more important, aspects of image quality were negatively affected.

For me, music is sound, accurate spatial reproduction is a secondary, almost superfluous, effect.

 

Let’s be realistic. We are talking about music. How to have a better listening experience for music. I am not talking about recreating a real virtual sound machine which serves no purpose for this hobby although it works far better when implemented along 5.1 multichannel. 

 

I usually refer to live unamplified concert hall sound. Even if we take a small Jazz it is still the same. The original direct sound is only about 60 to 120 degrees wide in front of you. A conductor may perceive 120 degree and a person who sits in the 50th row would have about 60 degrees or less  width. 

 

The rest of the sound that reaches your ears are not the direct sound. It has been established long ago which of the reflection, what time difference, how much delay , comb filtering and more of others that really matter for the perception of music in concert hall. 

 

And it it also has been established that that not all of the lateral reflection and reverberation matters as we our brains disregard them. So it doesn’t matter if you reproduce or don’t reproduce them. 

 

No no need for the crazy sphere. Just get the Smyth Realizer. Btw, how old is the research?

[fas42]

The ear/brain reacts to all the acoustic information it picks up in the natural world around it, and has very little trouble distinguishing various sound sources, and locating them in the 3D world around oneself - all the tiny clues are present, and from a lifetime of hearing experience can make smart guesses, attribute the sounds from certain sources. The acoustic information is minute - right at this very minute there's a group of birds outside, cockatoos, wheeling around and sitting in trees - the doors are closed, the sound is coming through glass - but I can pinpoint where those birds are, with ease; and whether they're coming or going. Now, how clever is our hearing system to be able to do that so easily, with such "poor information" as I'm getting?

 

That information is on the recording to a sufficent degree for our brains to make sense of it - it's been endless times that I've listened to recordings I know well on other systems - and on them the particular audio world on the recording has shrunk down to a miserable cardboard cutout of what's actually there - I might as well have ear protection muffs on, in terms of what I'm getting from that playback ...

[fas42]

12 minutes ago, STC said:

 

Let’s be realistic. We are talking about music. How to have a better listening experience for music. I am not talking about recreating a real virtual sound machine which serves no purpose for this hobby although it works far better when implemented along 5.1 multichannel. 

 

...

 

No no need for the crazy sphere. Just get the Smyth Realizer. Btw, how old is the research?

 

No need for crazy spheres, or clever headphone playback. Two speakers can do what the Smyth device does, only better - as an example, you can leave the room, and come back in - and that experience matches how it would work with a "live show".

[mansr]

Whatever drugs you are smoking, can I have some?

[STC]

2 minutes ago, fas42 said:

Two speakers can do what the Smyth device does, only better

 

Have you tried the Smyth? A properly setup 5.1 SACD with true multi channel recording will win hands down over a two channel stereo. 

[fas42]

17 minutes ago, STC said:

 

Have you tried the Smyth? A properly setup 5.1 SACD with true multi channel recording will win hands down over a two channel stereo. 

 

No, but I recognise the qualities described by the people who've tried them - well sorted multi channel will likely add to the experience, but I have never felt the need for the "extra" - well done stereo is so satisfying that the appetite is just not there for it.

[STC]

1 minute ago, fas42 said:

 

No, but I recognise the qualities described by the people who've tried them - well sorted multi channel will likely add to the experience, but I have neve felt the need for the "extra" - well done stereo is so satisfying that the appetite is just not there for it.

 

Ok. Now I understand. 

[fas42]

9 minutes ago, mansr said:

Whatever drugs you are smoking, can I have some?

 

The huge advantage I have over many people is that I "know", am 100% certain about, how good the reproduction can be - so even if I hear it done at a much less level I can "span the gap", and still get a buzz from the replay. Like listening to something you know on a bad car radio. This will never happen for someone who has not experienced the replay working that well - their "inner knowledge" can't add the necessary filler.

 

Everyone can get to that place, if they really want to - but they need to use the right approaches to sorting out their gear - most of the ways talked about are never going to be "good enough".

[mansr]

4 minutes ago, fas42 said:

The huge advantage I have over many people is that I "know", am 100% certain about, how good the reproduction can be - so even if I hear it done at a much less level I can "span the gap", and still get a buzz from the replay. Like listening to something you know on a bad car radio. This will never happen for someone who has not experienced the replay working that well - their "inner knowledge" can't add the necessary filler.

I can enjoy music on a terrible radio. I'll probably enjoy it more on a good system. Nevertheless, I'll never experience it the same as being at a live event.

[fas42]

3 minutes ago, mansr said:

I can enjoy music on a terrible radio. I'll probably enjoy it more on a good system. Nevertheless, I'll never experience it the same as being at a live event.

 

It will never be identical to the live event, but if you're after the kick that listening to live instruments can give one, then that is possible. If it sounds like the band is going full bore down the other end of the house, and you walk down, and into the room, and the impact is still fully there, of the real thing - that's the goal. If you go out into the street to listen, it sounds like you have a group "rehearsing" in your home - IOW, all the cues are realised that our hearing system has become attuned to reacting to, and the illusion is not broken.

[STC]

40 minutes ago, fas42 said:

 

The huge advantage I have over many people is that I "know", am 100% certain about, how good the reproduction can be - so even if I hear it done at a much less level I can "span the gap", and still get a buzz from the replay. Like listening to something you know on a bad car radio. This will never happen for someone who has not experienced the replay working that well - their "inner knowledge" can't add the necessary filler.

 

Everyone can get to that place, if they really want to - but they need to use the right approaches to sorting out their gear - most of the ways talked about are never going to be "good enough".

 

In a way, we are in the same boat. How do we convince others? The difference between you and I is whether what we do is repeatable?

 

I can always demo what I do with a click of mouse to compare A and B configuration. As you know, I was very keen when you first started to post and roll your videos seriously only to find it showed nothing that an average human being could decipher. 

 

You have to come up with evidence so that others could repeat. 

 

For an example, when I said the reverbs should come from the side I could demo them. Actually, Toole did a more elaborate experiment to prove the point.

 

In my case, it is simply to let the listeners evaluate them. I could play a basic stereo sound and then just turn on the 90 degrees convolution speakers.  Ask them whether they perceive any difference? Is the difference is positive or negative? Then I mute the 90 degrees speakers and turn on the convolution speakers at 45 degrees and I ask for their opinion. 

 

It is is not only what I hear matters but what others could is more valuable.

 

You have to  show something like this so that others could repeat and confirm. Otherwise, all your knowledge is nothing more than....conjecture only you could hear. 

[fas42]

41 minutes ago, STC said:

 

In a way, we are in the same boat. How do we convince others? The difference between you and I is whether what we do is repeatable?

 

I can always demo what I do with a click of mouse to compare A and B configuration. As you know, I was very keen when you first started to post and roll your videos seriously only to find it showed nothing that an average human being could decipher. 

 

You have to come up with evidence so that others could repeat. 

 

For an example, when I said the reverbs should come from the side I could demo them. Actually, Toole did a more elaborate experiment to prove the point.

 

In my case, it is simply to let the listeners evaluate them. I could play a basic stereo sound and then just turn on the 90 degrees convolution speakers.  Ask them whether they perceive any difference? Is the difference is positive or negative? Then I mute the 90 degrees speakers and turn on the convolution speakers at 45 degrees and I ask for their opinion. 

 

It is is not only what I hear matters but what others could is more valuable.

 

You have to  show something like this so that others could repeat and confirm. Otherwise, all your knowledge is nothing more than....conjecture only you could hear. 

 

All fair enough points, ... there are many ways to "fool the brain", and mine is perhaps the simplest, and also hardest, method. Simple, because it merely requires a conventional audio setup; hard, because that setup has to have all audible weaknesses eliminated - the direct sound can never show any abnormalities, because if they are there the brain seizes upon them, and rejects the illusion. Masking by additional sound sources is not there to save the day, the representation stands or falls by what emerges from the drivers on the two sides.

 

This makes it hard to demonstrate the situation - audio recorded of the playback sounds, or should, just like the recording, over the same method of monitoring - the photocopy matches the original. The difference between the sound being good enough, and not being good enough, may be so subtle over the sound system used to monitor by others, to be meaningless.

 

That said, I might do some more rounds with something more extravagant, like a brass band recording - and record directly in front, and in various locations more distant from the sound - outside the room, outside the house, etc.

 

The repeatability is the the hard thing for others to master - they need to be able to honestly assess where the audible weaknesses of their setups are, and then work toward resolving them; this is the way I got the "good stuff" the first time, and every system will be different - no easy answers.

[gmgraves]

6 hours ago, STC said:

 

If your brain could filter the unwanted sound at the listening location why suddenly it becomes dumb and unable to filter the same sound over the loudspeakers. 

 

You observation is correct but the reasoning is wrong. 

 

Why don't you rethink that a little bit? You put on a recording of a live performance. One that you like. About 15 minutes into the performance, somebody coughs violently. Guess what? Every time you play that recording, there will be that expectational anxiety: "Here it comes!" If you are sitting in a concert hall, listening to a live performance, you can ignore that coughing spell, after all you'll never hear it again. But if it's in a recording, you'll hear it every time and you'll hate it every time. Listening to a recording just isn't the same thing as listening to a live event. I find it more than a little telling that somebody has to explain that to you!

[gmgraves]

3 hours ago, fas42 said:

 

It will never be identical to the live event, but if you're after the kick that listening to live instruments can give one, then that is possible. If it sounds like the band is going full bore down the other end of the house, and you walk down, and into the room, and the impact is still fully there, of the real thing - that's the goal. If you go out into the street to listen, it sounds like you have a group "rehearsing" in your home - IOW, all the cues are realised that our hearing system has become attuned to reacting to, and the illusion is not broken.

 

Funny, to me the illusion is never completely there to begin with. I've been privy to a lot of really expensive, first rate systems, and none have ever even half convinced me that I'm listening to live music playing in a real space. Oh, don't get me wrong, I have heard many a stereo system that I found satisfying as a listening experience as is my own, but live instruments? Not really. I was listening to Mario Martinez' (PlayClassics.com) recording of Angel Cabrera playing Debussy on a concert grand piano the other evening, and I got glimpses of reality, but that illusion wasn't really very stable and didn't last long.