Audio Blind Testing

[audiventory]

1 hour ago, firedog said:

You can't compare an SACD that isn't produced from actual hi-res to CD and then conclude that people can't hear the difference betweeh hi-res and Redbook, because you aren't comparing actual hi-res to Redbook. So their test didn't prove what they were trying to or what is claimed for it.

 

Comparison of high resolution, SACD and CD is technically impossible. Even for single DAC. Because different electrical circuits work for each of these modes (see "PCM versus DSD DAC" part): https://samplerateconverter.com/educational/what-dsd

[audiventory]

5 hours ago, fas42 said:

you mean the player, DAC, preamp, speakers, room, setup skills have absolutely nothing to do with it ... ?

 

I meant that comparison of 2 resolutions or DSD vs. PCM is technically non-correct (methodologically impossible) in general case. It do not depend on equipment.

[audiventory]

21 minutes ago, fas42 said:

I was agreeing with you, but made a poor attempt at humour, regarding how people can "know" what is the cause of something being better or worse in a complex system, when there is almost no information

 

It is reason, why I very careful to results of any tests. Here example of careful test http://www.enjoythemusic.com/magazine/viewpoint/0716/High_Resolution_Audio_Perceptual_Evaluation/

I consider it as learning of certain case (hardware+software) only. But the test methodology and execution are done very carefully.

[audiventory]

1 hour ago, pkane2001 said:

Why is it that I can't compare analog output produced from DSD to that produced from PCM?

 

We can compare format implementation.

But we can't compare formats as itself.

 

Example #1:

 

It mean that all the cases are possible:

1) PCM better DSD

2) DSD better PCM

3) No difference

 

We can't claim that DSD better PCM (and contrary) for all cases.

 

Example #2:

 

1) 24 better 16 bit

2) 16 better 24 bit

3) No difference

 

We can't claim that 24 better 16 bit (and contrary) for all cases.

[audiventory]

9 minutes ago, pkane2001 said:

But, if you pick some specific factors to compare, you can certainly make a comparison and reach a conclusion that one format is better than the other in respect to these factors. For example, noise levels, frequency response, dynamic range, etc.

 

Format (description and figures) declare approximatelly technical potential.

Implementation can release the potential or not.

 

If we compare DSD and PCM we can't compare noise level, dynamic range, frequency response. Because noise shaping may be applied different ways.

 

When we compare 24 and 16 bit implementation, we compare also clock generators' stability, noise of amplifier chips into DAC, etc.

 

When we compare mathematically modeled signal that stored into 16 and 24 bit files, we can discuss about format comparison in digital domain.

 

When we compare mathematically modeled signal that stored into PCM and DSD files, we can't discuss about format comparison in digital domain, because implementation of noise shaping is matter.

[audiventory]

16 minutes ago, gmgraves said:

system that sounds like live instruments playing in a real space

 

Unfortunatelly, single instrument sound differently at:

1. different locations of same concert hall;

2. different concert halls.

 

In the best (impossible [in exact demands] at current technical level) case we can reproduce how it sound at:

    given location of

    given concert hall for

    given capturing device (currently, it is microphone).

 

Read more https://samplerateconverter.com/content/where-limit-audio-quality

[audiventory]

6 hours ago, gmgraves said:

That's irrelevant. A system that sounds exactly like music would sound like a piano or a violin or a trumpet no matter where in the concert hall it was.

 

1. Sound is a wave field.

 

2. Musical instrument is omnidirectional wave source.

 

3. Sound of the musical instrument is sum (interference) of acoustic rays in listening point.

 

4. The acoustic rays are:

  - direct (from source) and

  - bounced from surfaces of concers hall.

 

5. Concert hall impact to sound of musical instrument by distance to listening point and bounced rays.

 

Conclusion:

Musical instrument sound differently in different concert hall.

[audiventory]

7 hours ago, gmgraves said:

No reproduction system is so good that it would fool anyone into thinking that they are listening to live musicians playing in a space where there is nothing between the musicians playing and the listener's ears but air. T'ain't gonna happen!

 

In my quote, that you commented, present words "impossible [in exact demands] at current technical level".

[audiventory]

5 hours ago, gmgraves said:

Then the perfect system would make them sound different when recorded in different concert halls. But the perfect system would always sound like that instrument played in that hall, it wouldn't make, for instance, a violin sound like a trumpet. It would always sound like a violin, and you, as the listener would always recognize it as a violin.

 

Difference sound between violin and trumpet is not matter even for old systems. There too big difference in initial wave forms, generetad by the instruments.

 

But we don't know reference sound of the violin as itself.

 

In ideal case we know how it sound in:

a) our head and memory;

b) the concert hall;

c) the location of the concert hall.

 

 

 

[audiventory]

41 minutes ago, fas42 said:

 

But we have built a memory of the distinctive qualities of the sound of these instruments, from a lifetime of exposure to the sounds. If we are about to walk into a room, where a real instrument is playing, we are absolutely certain about what we will see, even from just a whiff of the sound.

 

It is no matter of instrument recognizing. I suppose, trained people can distinguish recorded sound of certain violin instances. I think, it is not matter for old audio systems even.

 

Different concert halls have audible sound difference.

Extremal example: compare sound in a room with big glass surfaces, a room with brick walls, a room with furniture and a room with carpets.

 

As example, we discuss, PCM vs. DSD: what is more "natural"?

It is not matter "what is instrument"?
But now main problem of recording/playback systems is wave field reproduction, that finally bring sound form concert hall to our ears in our listening room.

[audiventory]

 

29 minutes ago, gmgraves said:

The ideal system will accurately reproduce all performances of all music from all venues. No matter what our memory tells us, no matter what concert hall the performance took place in, or where that concert hall is. We don't need to know the reference sound of a violin. When we attend a live concert where there is nothing between our ears and the musical instruments being played, we don't questions these things, we just listen. The ideal, perfect system (which doesn't exist) will reproduce music in such a way that everything between our ears and the musical event to which we are listening disappears. There would be no difference between us sitting in the best seat in the house, listening to the concert live, and us sitting in our easy chair in our listening room listening to the concert being reproduced there. That cannot be done, not today, and probably not tomorrow.

 

Way to implement "ideal system" is re-produce sound hologram of concert hall.

 

The "hologram" term is not abstract.

 

"Sound hologram" is acoustic wave field in given point of concert hall.

 

It is absolutely same to optical hologram. Because both terms are based at common wave theory (physics).

[audiventory]

28 minutes ago, STC said:

Trained people could not even recognize the so-called superior sound of Stradivarius violin.

 

I don't met some researches of the same instrument recognition. But Stradivarius sound differently then cheap violin, isn't it?

[audiventory]

2 minutes ago, fas42 said:

What most people don't appreciate is that it's the little things in the sound that matter, not the big things - our ears are a harsh mistress ...

 

Our ears and brain are big "sound changers". There ideal system can't help us

[audiventory]

2 hours ago, fas42 said:

Which means a reproduction system only has to reach a certain quality, that corresponds roughly to the live thing - and we "hear the illusion".

 

I'm agree. Objectively (measurable with some precision) ideal audio system can re-produce the sound hologram next the ears.

But it don't guarantee, that we listen same sound after the ideal reproduction.

[audiventory]

7 minutes ago, gmgraves said:

An accurate stereo system will let you clearly hear the difference between a well-recorded Stradivarius, a Guarneri, and an Amati as well as that cheap violin and in today's world do that without fooling you that are listening to these instruments live! 

 

I have some experience with oboes as oboist long long time ago. Though, I'm not sure, that currently I can exactly distinguish the oboe models. Pianos have very different sound. It is reasons, why I think, that experts can detect instrument kind even by sound.

Modern audio systems produce recorded sound very good (by distortions). I really love it. But, for me, it is not same to environmental "live" sound by wave field issues. Wave field reproduction is principial and very important thing currently in my opinion. Because, I think, it allow us to move forward next big step in HiEnd audio.

[audiventory]

1 hour ago, STC said:

In nature there is no stereo sound and therefore you cannot reproduce live performance accurately with two speakers stereo. However, if you were to channel each sound to a single speaker and placed them accordingly as in live performance, it should sound as good as live performance.

 

Channel number is not base of sound hologram reproduction.

 

For design hologram reproduction system we define reproducing field precision.

 

And after we account room configuragtion/construction.

 

The design algorithm have output:

1) Channel number;

2) Channel speaker locations.

[audiventory]

25 minutes ago, STC said:

In short, 2 speakers are not enough for realistic live performance. 

 

Depend on desired precision of sound hologram.
 

25 minutes ago, STC said:

Many known product which can do this?

I don't know ideal systems. There are issues, that I don't know: how to implement currently.

[audiventory]

37 minutes ago, STC said:

So you are talking about a system that you have not heard? How can you even be sure that it will sound like live performance?

 

It is not matter how it sound. It is matter acoustic wave field reproduction.

 

With ideal system we have identical "live" and "reproduced" physical impacts to ears (sound field/sound hologram close to ears).

[audiventory]

21 minutes ago, STC said:

Are you referring to this?

 

Wave field (sound hologram) is complex oscillation of acoustic waves in each point of 3D-space.

 

Theoretically and practically (in some appoach to ideal) we can manage the oscillations in single or several points (about each ear or ears of several listeners). It is synthesis of sound field (sound hologram).

 

Currently only headphones close to implementation of playback part of such system.

 

Speakers generate many bounced acoustic rays, that distort synthesed hologram.

 

 

[audiventory]

6 hours ago, fas42 said:

What all this thinking fails to take into account, is that the ear.brain is capable of compensating for a "non-ideal" wave field reproduction to a very great degree.

 

For claiming this need measurable evidences.

[audiventory]

4 hours ago, semente said:

To reproduce it you must first be able to capture it.

 

Exactly. It is also problematic part.

[audiventory]

5 hours ago, semente said:

One is enough. You need one of these per instrument reproducing an anechoic recording:

 

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.

[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.

[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.