Audio Blind Testing

[audiventory]

16 minutes ago, Ralf11 said:

I say 2 crossed mics and just ride the gain controls...

 

If you mean 2 mic at head dummy, it is most close thing to proper wave field capturing system today.

 

It is far from 100% ideal capturing. But it is easy to use, as it must be.

 

However, playback acoustic wave interferention is solved partitially in headphones only.

[esldude]

6 hours ago, fas42 said:

 

Not really. Imagine you were in the studio, listening to the master tape, or console, with all the individual tracks that were combined in the final mix at your disposal - playing through a high quality monitoring speaker setup. You can solo any one of those tracks, and hear exactly what was captured on that "stage", with the added effects - with the listening, on a competent rig, that's the subjective impact: all the individual elements can be soloed, or you just let the whole flow over one. Just like being in the middle of a group of musicians fooling around; you can listen to one, and ignore the other fiddlings - the cocktail party effect ...

Typically when you do such you next have the guy at the console add some reverb or delay to "glue" the mix together.  There are a number of tricks to this by experienced people, and it goes against your hearing what you are describing here. 

[fas42]

4 hours ago, gmgraves said:

 

How much live recording have you done? Because I'm here to tell you that it's not all captured and I will guarantee that!  the power of brass is not captured, ever via any known technology. A recorded orchestra, for instance never has the awesome energy that the actual performance had - can't be done. Recordings, even 32-bit recordings do not have the dynamic range of a full symphony orchestra; It's just impossible.  Even if the digital recording format could register the full dynamic range of the orchestra, the microphones can't and don't! And for you to keep insisting that recordings capture everything and all one needs is a fas42 approved playback system and it will get played back perfectly, is ludicrous and just confuses people. 

 

How do you know it's not captured? The only way you can assess this is by listening to playback, and that's where the problem lies!

 

One doesn't need "perfect" playback, one needs it to meet a certain standard - and there is a process that can be followed, to evolve a system to that level. Most rigs won't do high SPLs without very distinctive issues; there's very obvious, audible problems heard - and your brain tells you this, and you're not fooled.

 

The faster a car can travel, the better engineered the suspension has to be, so that you, the driver retain full control at all times - the "best" vehicles are not those with the biggest engines, but those which can operate in the full speed range with complete predictability.

[fas42]

1 hour ago, esldude said:

Typically when you do such you next have the guy at the console add some reverb or delay to "glue" the mix together.  There are a number of tricks to this by experienced people, and it goes against your hearing what you are describing here. 

 

There may be "glue" added, but this doesn't prevent "ungluing" by the brain - the better the playback, the easier this is - the individual parts can be picked apart, and 'watched' as easily as following a particular live musician in front of you. Michael Jackson's Bad is a good example of where one can completely separate the component parts, mentally - the machinery of what creates the feel of each track is completely exposed.

[fas42]

3 hours ago, audiventory said:

 

For claiming this need measurable evidences.

 

The field of Auditory Scene Analysis explores this behaviour aspect of human hearing, has been studied for about 20 years. Simply put, if something is missing, and the brain "knows" it should be there, from other clues - then, it is there!

[semente]

8 hours ago, STC said:

 

All recordings add a little reverb to sound natural. Non processed recording such as live concert hall already got huge amount of reverbs in them. 

 

This ambience from the concert hall is more accurately reproduced in near anechoic conditions because your own room's acoustic signature.

 

We've discussed this twice already, I need to find my previous posts.

 

But to really reproduce the sound field of an acoustic instrument which radiates in every direction you need one of those driver covered spheres and also as many mics as the drivers placed 360° around the instrument and record it in free field conditions (anechoic).

 

This is impractical but fortunately we have stereo.

[semente]

8 hours ago, gmgraves said:

 

That doesn't work. You want to capture the sound field not the individual instruments. Between the musicians and your ears (and you have only two) the sound melds into a cohesive whole, sure the whole has disparate parts, but they must interact in the air in order to give a palpable performance.

 

I know that.

But it's not possible to achive a facsimile of the original acoustic event. So two- or multi-channel stereo will have to do.

[semente]

9 hours ago, STC said:

 

All recordings add a little reverb to sound natural. Non processed recording such as live concert hall already got huge amount of reverbs in them. 

 

An anechoic recording can can sound accurate provided the room reverbs is at the correct ratio and the sound from the source radiates 360 degrees like in live performance. 

 

Since you you are trying to reproduce the live sound in your room using anechoic recordings, the reverbs need to high and at that level other normal recordings with its own reverb will sound a tad too bright. 

 

Live performance can can be accurately recaptured using binaural microphone and reproduce somewhat accurately with headphones although the very fact that requires you to wear headphones alters the perception of live sound. 

 

What matters to our ears is only the tiny sound arriving at our ears. If you capture them at the spot and replay the at the spot that 100% accurate with accurate headphones. 

 

Having said that, it still lacks other sound that reaches our head through bone conduction and vibration sensation that stimulates the body. 

 

Live performance can can only be recreated with multi channels/ speakers approach for ensemble and for solo instrument which is essentially mono can sound realities with single speaker. 

 

 

 

Here's the topic:

 

https://www.computeraudiophile.com/forums/topic/32135-beyond-stereo/

 

 

On 20/06/2017 at 9:38 AM, semente said:

 

But my point is that current 3D/ambio audio is still nothing like "real" sound.

 

Look at the dispersion pattern of a cello.

 

How can you expect to mimic this behaviour without recording a sphere of sound and then reproduce it using something like this?

 

 

Your friend explained this in the other thread:

 

 

On 19/06/2017 at 7:21 PM, Ralph Glasgal said:

Unfortunately human hearing expects that the direct sound and reflected sound be logical and physically possible.  Room reflections and reflectons from seats and heads in a concert hall are not all that different. But what stimulates them is.  In the concert hall the interarual level differences and the interaural time differences of early reflections correlate with the horizontal position of an instrument on the front stage. At home, with reflected sound coming from two fixed speakers these room cues are a form of acoustical nonsense.  There are other psychoacoustic issues as well such as long period reverb, diffuse tails, etc.

 

On 20/06/2017 at 9:41 AM, semente said:

Looks like someone is already working on this:

 

 

These Spherical Microphone Arrays Make Holographic Images of Sound 

http://gizmodo.com/these-spherical-microphone-arrays-make-holographic-imag-1741535712

[STC]

48 minutes ago, semente said:

This ambience from the concert hall is more accurately reproduced in near anechoic conditions because your own room's acoustic signature.

 

This is a common misconception. Ambience of concert hall arrives your ears from millions of direction. The most important reflection being the side reflection. 

 

To reproduce the live performance of concert hall you need to replicate the sound reflecting from various surface to reach your ears. 

 

Normal recorsing will will have little reverbs adds and rest of the reverbs expected to come from you room. In small rooms, the reflection can be overbearing and uneven. If you can address those then you have a realistic concert hall in your room with multi channel recordings. 

 

 

[semente]

6 hours ago, audiventory said:

 

The such speaker design must provide omnidirectional managed (with 1 acoustic wave ray precision) radiation.

Ray is path of acoustic wave. The can consider rays as radiation from infinite small square of the speaker surface.

It is spherical single driver, rather then several drivers.

Because musical instrument have no equal radiation in all directions.

Anechoic room is not customer suitable. So direction manage is need for room adaptation.

 

This is what I meant.

 

You can't capture and/nor reproduce the sound of an acoustic instrument in a reverberant space.

(because your speakers will not be able mimic the radioation pattern of the instruments nor the reflections of the original venue)

 

But

 

You can capture and reproduce the sound of an acoustic instrument in an anechoic space.

(with the mic sphere and spherical speaker I showed)

[semente]

30 minutes ago, STC said:

 

This is a common misconception. Ambience of concert hall arrives your ears from millions of direction. The most important reflection being the side reflection. 

 

To reproduce the live performance of concert hall you need to replicate the sound reflecting from various surface to reach your ears. 

 

Normal recorsing will will have little reverbs adds and rest of the reverbs expected to come from you room. In small rooms, the reflection can be overbearing and uneven. If you can address those then you have a realistic concert hall in your room with multi channel recordings. 

 

 

 

And you cannot replicate the reflections of the hall unless you have a dedicated channel for ever sigle one of them:

 

 

Even you Ralph G agrees with that.

 

 

Because your speaker's dispersion pattern is radiating these reflections from the wrong spot, or radiating both direct sound and cues from the same spot, it is not possible for it to replicate the original event.

 

On top of that sound coming out of your speaker is generating it's own reflections off the room's boundaries which whilst adding "noise" to the reproduction (perhaps subjectively improving the perception at the listening spot) is also steering it away from what was listened at the original event (the replication):

 

[semente]

I'll reinstate that current 3D/ambio audio is still nothing like "real" sound.

 

It perceptually increases a sense of space, but it's a mere effect that creates other problems, affecting aspects of music reproduction which I find far more relevant: music is aural (sound) not visual (space).

[STC]

17 minutes ago, semente said:

Even you Ralph G agrees with that

 

Is it necessary for such remark?  

 

I thought of  discussing more about research on emotion when listening to live performance and so forth but nevermind. 

 

I am am not saying it is hundred percent  of X concert hall sound but realistic 3D sound can be achieved in Y concert hall as replicating the ambience is possible. 

 

I am doing this regularly. It took me 5 years to get it right. When was the last time you attempted successfully? You have not listened to a true 3D sound reproduction and your opinion is nothing more than anecdotal. 

 

[semente]

7 minutes ago, STC said:

 

Is it necessary for such remark?  

 

I thought of  discussing more about research on emotion when listening to live performance and so forth but nevermind. 

 

I am am not saying it is hundred percent  of X concert hall sound but realistic 3D sound can be achieved in Y concert hall as replicating the ambience is possible. 

 

I am doing this regularly. It took me 5 years to get it right. When was the last time your attempted successfully? You have not listened to a true 3D sound reproduction and your opinion is nothing more than anecdotal. 

 

 

As I've written in my previous message, I am not denying that ambio may produce exciting spatial effects, but there are other aspects of sound reproduction that I value more.

Replication is not possible.

[esldude]

I think some people have in mind this idea stereo sound can work like holography.  That two sources might set up an interference pattern replicating the actual sound field recorded.  It doesn't work this way however.  It is using how our hearing works to perceptually trick it,  not recreate an actual sound field.  

 

Now holography creates a pair of sources in light that interfere around objects and record that interference pattern that can be recreated with laser light. I think for the same idea to work with sound on the playback end, it might work best if we had a defined area of ultrasonic sound that could be modulated to produce such an interference pattern.  The modulation would be something like class D amps only in the air.  It does NOT work with audible frequencies because they vary too much in length so no stable interference pattern can be established.  

 

Even if you managed this for playback, I am not sure how it would be accurately recorded.  It might be created from nothing for pop type music.  Not sure how you would record it in a venue however. 

 

There has been some work in sound field reconstruction at least back to the 1920's and 1930's.  You end up needing so many channels it is impractical.  

[STC]

19 minutes ago, esldude said:

 

I think some people have in mind this idea stereo sound can work like holography.  That two sources might set up an interference pattern replicating the actual sound field recorded.  It doesn't work this way however.  It is using how our hearing works to perceptually trick it,  not recreate an actual sound field.

 

 

Almost all audiophiles are thinking that’s  possible and regularly claiming hearing so. 

 

Stereo binaural is close enough to 3D but since it comes from headphones it is hard to project the main image in front of you like how you witness them in live performance. 

 

 

Imagine the same sound coming from your two speakers. That’s the first step. The next step is to reproduce the ambiance of the concert hall. The more impulse response the more accurate it is. That’s the second stage. 

[esldude]

18 minutes ago, STC said:

 

Almost all audiophiles are thinking that’s  possible and regularly claiming hearing so. 

 

Stereo binaural is close enough to 3D but since it comes from headphones it is hard to project the main image in front of you like how you witness them in live performance. 

 

 

Imagine the same sound coming from your two speakers. That’s the first step. The next step is to reproduce the ambiance of the concert hall. The more impulse response the more accurate it is. That’s the second stage. 

So are you saying because many claim it they are managing to recreate soundfields?  

 

I have said before binaural just doesn't work for me.  This one didn't either.  Sounded much better and more dimensional over my speakers actually.  

[audiventory]

1 hour ago, semente said:

You can't capture and/nor reproduce the sound of an acoustic instrument in a reverberant space.

(because your speakers will not be able mimic the radioation pattern of the instruments nor the reflections of the original venue)

 

But

 

You can capture and reproduce the sound of an acoustic instrument in an anechoic space.

(with the mic sphere and spherical speaker I showed)

 

Except capturing to 2-microphones in head-dummy "ears" with playback on headphones.

 

It is not exact way, but available right now.

[STC]

21 minutes ago, esldude said:

I have said before binaural just doesn't work for me.  This one didn't either.  Sounded much better and more dimensional over my speakers actually.  

 

There are about 5% of the population couldnt perceive the 3D TV image. It maybe possible the same thing happening to binaural sound. Perhaps, in another 10 years or so we will hear research on that. 

[pkane2001]

1 hour ago, esldude said:

I think some people have in mind this idea stereo sound can work like holography.  That two sources might set up an interference pattern replicating the actual sound field recorded.  It doesn't work this way however.  It is using how our hearing works to perceptually trick it,  not recreate an actual sound field.  

 

Now holography creates a pair of sources in light that interfere around objects and record that interference pattern that can be recreated with laser light. I think for the same idea to work with sound on the playback end, it might work best if we had a defined area of ultrasonic sound that could be modulated to produce such an interference pattern.  The modulation would be something like class D amps only in the air.  It does NOT work with audible frequencies because they vary too much in length so no stable interference pattern can be established.  

 

Even if you managed this for playback, I am not sure how it would be accurately recorded.  It might be created from nothing for pop type music.  Not sure how you would record it in a venue however. 

 

There has been some work in sound field reconstruction at least back to the 1920's and 1930's.  You end up needing so many channels it is impractical.  

 

Dennis, so are you saying that for a true 'live' sense and feel of reproduced audio, the listener must be able to move through the sound field and sample this field at slightly different points to get the correct illusion? Similar to holography that looks  2D if you just look at it from a single point, but becomes 3D as you start moving your head around it?

 

If that's the case, would I also get only 2D, not truly 'live' sound impression at a concert hall if I sit with my head perfectly still?

[semente]

1 hour ago, pkane2001 said:

 

Dennis, so are you saying that for a true 'live' sense and feel of reproduced audio, the listener must be able to move through the sound field and sample this field at slightly different points to get the correct illusion? Similar to holography that looks  2D if you just look at it from a single point, but becomes 3D as you start moving your head around it?

 

If that's the case, would I also get only 2D, not truly 'live' sound impression at a concert hall if I sit with my head perfectly still?

No. In the hall you immersed in reality. Perception of source location is given by phase and level and time differences between ears and by ambience cues.

[pkane2001]

21 minutes ago, semente said:

No. In the hall you immersed in reality. Perception of source location is given by phase and level and time differences between ears and by ambience cues.

 

Then what is it that's not being recorded by microphones? Phase? Frequencies? Ambience cues, reverb, reflections, even sound wave interference all translate into a set of frequencies with a certain phase relationship. If we can record all the necessary frequencies and their phase relationship, then what's missing?

 

[bhobba]

On 08/01/2018 at 3:03 AM, Kal Rubinson said:

I agree.  Where did we determine if there is a difference?  So far, we have only subjective and anecdotal opinions.   

 

You want to know why?

 

I have participated in and helped organise such tests.

 

First they are very difficult and time consuming to do.  Plus one little mistake renders them invalid.   In the last one I was involved in it was ruined because a DAC that  performs best grounded was not grounded by a simple error in not being careful what power point it was plugged into.   Weeks and weeks of work went into this - all ruined.

 

There are huge egos involved in it - the winner will reap the rewards - the losers will greatly suffer.  There is nothing really in it for anyone - except those that really count - us.   The only way it gets done is if people and their friends spend their own money getting the gear.   I have done it, but boy after a while you get sick and tired of forking out your own money.   Manufacturers will not help you - as I said they have a lot to loose.  

 

To anyone that is a blind test enthusiast - do one and report what happens here.   That way you will see exactly what the issues are.

 

Thanks

Bill

[semente]

44 minutes ago, pkane2001 said:

 

Then what is it that's not being recorded by microphones? Phase? Frequencies? Ambience cues, reverb, reflections, even sound wave interference all translate into a set of frequencies with a certain phase relationship. If we can record all the necessary frequencies and their phase relationship, then what's missing?

 

 

The pair of mics is capturing what someone in the audience would have listened but the speakers (in a room) will not be able to recreate the soundfield of original event as it was listened.

 

See these posts:

 

https://www.computeraudiophile.com/forums/topic/38125-audio-blind-testing/?do=findComment&comment=766034

 

https://www.computeraudiophile.com/forums/topic/38125-audio-blind-testing/?do=findComment&comment=766027

 

https://www.computeraudiophile.com/forums/topic/38125-audio-blind-testing/?do=findComment&comment=766030

 

 

[Kal Rubinson]

36 minutes ago, bhobba said:

 

You want to know why?

 

I have participated in and helped organise such tests.

 

First they are very difficult and time consuming to do.  Plus one little mistake renders them invalid.   In the last one I was involved in it was ruined because a DAC that  performs best grounded was not grounded by a simple error in not being careful what power point it was plugged into.   Weeks and weeks of work went into this - all ruined.

 

There are huge egos involved in it - the winner will reap the rewards - the losers will greatly suffer.  There is nothing really in it for anyone - except those that really count - us.   The only way it gets done is if people and their friends spend their own money getting the gear.   I have done it, but boy after a while you get sick and tired of forking out your own money.   Manufacturers will not help you - as I said they have a lot to loose.  

 

To anyone that is a blind test enthusiast - do one and report what happens here.   That way you will see exactly what the issues are.

 

Thanks

Bill

Yeah.  Been there, done that.