Measurements & Sound Quality

[Ralf11]

not temperature or time

[fas42]

3 minutes ago, bluesman said:

Isolating the instruments greatly reduces intermodulation between & among them, and a damped environment further reduces extraneous input from resonance etc. Playing each individual instrument, closely miked for recording to minimize bleeding, through its own speaker is the best way I know of to prevent intermodulation from contaminating the recording. It's closer to having the individual instruments in the playback setting.  That's why it sounds more like real instruments, but in the playback environment rather than the recording setting.

 

Amusingly, there are some 'experimental' recordings where only the stereo mike is used, and the balance between the instruments is fine tuned simply by adjusting the distance and positioning from that mike, of each musician. Strangely enough, it sounds very realistic - must be some powerful mojo happening in the space, to stop all that nasty intermodulation contamination.

[STC]

1 hour ago, esldude said:

Yep that will work.  I've done this using 5 musicians close miked in a damped environment.  Then play back over 5 speakers.  It can have a sound that is very real.  It sounds real in your room, not so much real like where it was recorded. 

 

This is similar to the experiment by Briggs and AR. This also shows that you don't need to capture all the radiation pattern of the instruments to recreate realism.

[esldude]

30 minutes ago, STC said:

 

This is similar to the experiment by Briggs and AR. This also shows that you don't need to capture all the radiation pattern of the instruments to recreate realism.

Yes I was thinking of both of those as I posted.  

[Summit]

9 hours ago, STC said:

 

In reproduced music (using stereo) we are recreating 1) the sound and 2) the position of the sound.

 

As far as to the accuracy of reproducing a single sound via a transducer, we achieved the threshold a long time ago where a recorded sound could convince animals whose survival depends on the ability to distinguish an extremely small difference in the sound which is beyond human capability. You can find research papers with spectrograms of real and recorded sound that were used in their studies.

 

In one such experiment where the scientists wanted to know how the parent penguin could identify their chicks among thousands of other chicks relied on a single transducer and managed to fool the parent thinking that they were their chicks call.

 

The real problem with reproduced music is creating the position of the instruments. In live performance (unamplified) we could locate the source based on HRTF. With stereo, to recreate the positional cues of different instruments it only uses one of the HRTF cues to recreate a phantom image. This is the difference between live and playback. Real image (position) is just one spot for each source in the live performance. However, with music, the phantom image is created by two speakers. The brain is continuously locating two sources to create a single phantom image. The process is contradicting how real sound in nature behaves and therefore itself is unnatural There is no way during playback of two speakers to recreate the soundfield or soundstage will ever be natural to us unless each instruments sound is confined to a single speaker.
 

Here is the video of the competing chicks call. The parent could reach them among thousands of calls. Initially, scientists thought the penguins uses some sort of physical landscape marking to identify the chicks location.

 

 

 

 

If the sounds like it comes directly from a tweeter or woofer it will not sound effortless and natural IME. We (normally) don’t want the sound of a piano or guitar to sound like it originated directly from the speaker(s) per se, even then it does. The reason is not only because of the stereo image, it’s because it sound unnatural in many other ways then it does. With a good stereo system the sound always seems like it is a bit free floating and not like it comes directly from its transducers, not even then they only use one woofer per speaker. With speakers that is 2, 3, 4 ways it would sound strange if some frequencies of the voice or guitar came from 2-4 different locations and is why the crossover frequency is so important to get right for everything over 80 Hz.   

 

Then you sit at a live concert you don’t really hear one spot only. The sound that actually reach you is a mix of many direct sound and some ambient sound.         

[STC]

1 hour ago, Summit said:

 

If the sounds like it comes directly from a tweeter or woofer it will not sound effortless and natural IME.

 

I understand what you are trying to convey here after reading your post till the end. However, reading this sentence in isolation may create some confusion as to the role of the speaker.

 

I intentionally left out from qualifying the term "spot" and "instrument" because that would lead to other areas of human perception of sound.

 

IMO, there is nothing wrong if the sound comes from the tweeter or woofer. That's how a speaker function anyway. In a normal two stereo setups (devoid of reflection) the image(s) will float between the two speakers. This is more natural compared to having all sound emanating from a single speaker. However, saying that sound shouldn't originate from the woofer itself is wrong as it depends on the size of the instrument itself.

 

A mouth is about 4 inches wide, and that's where the vocal originates.  If Norah Jones were to sing in front of you, the size of the sound would correspond to the size of her mouth. That's the same with a harmonica. The radiating surface is relatively the size of the woofer. The problem starts when you try to reproduce a piano or a drum set as they radiate from a large area or multiple spots. In this case, the sound of a single instrument will not have the large radiating surface, and we knew the size of piano due to prior knowledge of how a real piano would sound. This "unnaturalness" shouldn't be equated to inherent misinformation and confusion that the brain will have when creating phantom images. At most, this sounds 'unnatural" in a different sense because you are hearing an 8 foot Steinway piano sound coming from 1 foot piano (reference to a speaker size) and your prior knowledge knows that's not real.

 

[Kal Rubinson]

16 hours ago, bluesman said:

All reproduced music is a compromise

Of course but some forms are more compromised than others.

[semente]

On 12/20/2018 at 5:09 PM, sdolezalek said:

The problem is that we can measure a lot of things, but I'm not sure we know how to rank those measurements against each other in relative importance and then we don't really know what standard to compare them to. 

 

In my view, the problem is that measurements are unrelated to taste and what most people do is evaluate sound/performance according to their taste instead of assessing it from an observationist perspective, just as a biologist would describe a particular specimen or event.

[jabbr]

14 hours ago, Ralf11 said:

not temperature or time

Good point, particularly if you are measuring hot vs cool jazz as well as syncopation 

 

[bluesman]

3 hours ago, Kal Rubinson said:

Of course but some forms are more compromised than others.

Absolutely - and happiness is the ability to craft our compromises so that the pluses make us forget about the minuses! 

 

[crenca]

4 hours ago, semente said:

 

In my view, the problem is that measurements are unrelated to taste and what most people do is evaluate sound/performance according to their taste instead of assessing it from an observationist perspective, just as a biologist would describe a particular specimen or event.

 

On the contrary, measurements are very much related to taste.  The HP's I am presently listening (Focal Clears) are "clear" (a taste/subjective description) accurate (timbre, dynamics, etc.) and the CSD's, FR, distortion, etc. measurements all correlate to the subjective taste.  There IS a relationship after all.

 

The problem is the subjectist audiophile myth that measurements are "unrelated"...

[diecaster]

3 minutes ago, crenca said:

The problem is the subjectist audiophile myth that measurements are "unrelated"...

 

It's not that measurements and sound are unrelated. It's that that the measurements don't matter much because they don't measure what they need to measure to describe sound quality.

 

Transducers actually have more measurements that matter than say amps or preamps. But, frequency response measurements of a headphone don't tell you how the transducers sound. The standard measurements used to describe amps and preamps really mean nothing in the end. There are amps out there that sound like crap that measure fantastic and there are amps that measure adequately that sound incredible.

 

In the end, no matter how well or how bad something measures, you need to listen to it to know how it sounds. The measurements don't help hear.

[crenca]

15 minutes ago, diecaster said:

 

It's not that measurements and sound are unrelated. It's that that the measurements don't matter much because they don't measure what they need to measure to describe sound quality.

 

Transducers actually have more measurements that matter than say amps or preamps. But, frequency response measurements of a headphone don't tell you how the transducers sound. The standard measurements used to describe amps and preamps really mean nothing in the end. There are amps out there that sound like crap that measure fantastic and there are amps that measure adequately that sound incredible.

 

In the end, no matter how well or how bad something measures, you need to listen to it to know how it sounds. The measurements don't help hear.

 

Wrong, wrong and wrong.  These measurements are related, do matter, and do describe the sound and its "quality" to a strong degree.

 

Your just repeating radical subjectivism as an article of faith.  Measurements have a long and strong track record of direct and obvious correlation to the sound, and the whole audio/electronic industry depends on this correlation...

[diecaster]

15 minutes ago, crenca said:

 

Wrong, wrong and wrong.  These measurements are related, do matter, and do describe the sound and its "quality" to a strong degree.

 

Your just repeating radical subjectivism as an article of faith.  Measurements have a long and strong track record of direct and obvious correlation to the sound, and the whole audio/electronic industry depends on this correlation...

 

Just repeating? Dude, I have been listening to audio gear for over 40 years.

 

Here is what Nelson pass had to say in an interview:

 

"Measurements and listening go hand in hand. There is a correlation between objective and subjective, but they’re not strictly causal relationships. Clearly, there are some amplifiers that measure great with “standard” measurements but don’t sound so good, and there are examples of good-sounding/bad-measuring as well. The discrepancies are interesting because they point to either things that have not been measured—more likely, misinterpreted—or aspects of perception and taste that don’t correlate to measured flaws. Or both.

In the end, the subjective experience is what our customer is looking for. Our taste in sound may not appeal to everyone, but it’s what we have to work with, and we only need a small segment of the market to be successful. I don’t neglect the measurements; I put them to work."

[Ralf11]

6 hours ago, STC said:

 

A mouth is about 4 inches wide, and that's where the vocal originates. 

 

the vocal originates from the vocal chords, and is funnel thru the mouth

[Ralf11]

2 hours ago, jabbr said:

Good point, particularly if you are measuring hot vs cool jazz as well as syncopation 

 

 

charm, color and spin are the really hard things to measure - not to mention that big scalar value that's like... all over, man

 

and lest anyone think that doesn't matter for music... I refer them to Francis Vincent Zappa and The One Big Note

[crenca]

8 minutes ago, diecaster said:

 

Just repeating? Dude, I have been listening to audio gear for over 40 years.

 

Here is what Nelson pass had to say in an interview:

 

"Measurements and listening go hand in hand. There is a correlation between objective and subjective, but they’re not strictly causal relationships. Clearly, there are some amplifiers that measure great with “standard” measurements but don’t sound so good, and there are examples of good-sounding/bad-measuring as well. The discrepancies are interesting because they point to either things that have not been measured—more likely, misinterpreted—or aspects of perception and taste that don’t correlate to measured flaws. Or both.

In the end, the subjective experience is what our customer is looking for. Our taste in sound may not appeal to everyone, but it’s what we have to work with, and we only need a small segment of the market to be successful. I don’t neglect the measurements; I put them to work."

 

You probably have been buying into and repeating this "It's that that the measurements don't matter much because they don't measure what they need to measure to describe sound quality" Audiophile Myth for 40 years as well.

 

Pass does not back you up. He very clearly points to the correlation in the quote you choose (and says elsewhere that he and ever other designer utterly depends on it).  He is overstating the case here, perhaps because it is exactly as he says about "our customers" and "subjective experience".  He is playing to the crowd like any good politician or salesman.  Pass is a good salesman -  very very $successful$ in the all too subjectivised Audiophile market. 

 

Andrew Jones is more honest.  He openly admits he designs by measurements all the way to the end, and only "tweaks" by ear.  Measurements cover almost all of the design process because they are that good.  In today's consumer electronic world, that is how most things get done.

 

Audiophiles are like men standing on a new bridge next to the engineering who built it having this sort of discussion:

 

Audiophile:  "Measurements of physical phenomena did not get you very far in designing this bridge - enabling it to hold up your and mine weight did it"

 

Engineer:  "Why yes, yes they did"

 

Audiophile:  "But you don't understand all that much about sub-atomic particles, quantum flux, gravity waves, ubertanium and warp drive - not really"

 

Engineer:  "Um, true, but not really relevant..."

 

Audiophile:  "Be honest, you felt your way through designing and building this bridge.  What's your secret, fair dust?  Yep, it must be fairy dust holding us up..."

 

 

[Jud]

1 hour ago, crenca said:

Andrew Jones is more honest.  He openly admits he designs by measurements all the way to the end, and only "tweaks" by ear.  Measurements cover almost all of the design process because they are that good.  In today's consumer electronic world, that is how most things get done.

 

Since measurements are more accurate than the ear, I wonder what "tweaks" are needed.

[Jud]

1 hour ago, crenca said:

Pass is a good salesman -  very very $successful$ in the all too subjectivised Audiophile market. 

 

In one respect at least, he is more honest than anyone else I can readily think of.  He has released schematics for many, many of his designs.  So we are free to see what the design philosophy/circuitry is, dissect it to our heart's content, measure on simulator and/or actual build....

[fas42]

9 hours ago, STC said:

 

 

IMO, there is nothing wrong if the sound comes from the tweeter or woofer. That's how a speaker function anyway. In a normal two stereo setups (devoid of reflection) the image(s) will float between the two speakers. This is more natural compared to having all sound emanating from a single speaker. However, saying that sound shouldn't originate from the woofer itself is wrong as it depends on the size of the instrument itself.

 

Yes, the sound comes from the speaker. But our brain interprets all the auditory cues and positions the sound element "where it makes sense" to be. A playback system below par doesn't reproduce those cues precisely enough, with enough clarity - and the sound then obviously emerges from the speaker drivers, especially when you get a bit closer to them.

 

If one is able develop a rig to the point where the brain has enough information to continually maintain a convincing illusion, then there can be no going back. Normal stereo replay then becomes cartoon like, and has no special value as a listening experience, because it is so obviously "fake".

[fas42]

19 minutes ago, Jud said:

 

Since measurements are more accurate than the ear, I wonder what "tweaks" are needed.

 

The "tweaks" are the fairy dust holding up the bridge - because if done correctly they are actually enhancements and corrections to the poor design and implementation of the raw, audio system. An playback rig is like a bridge - the latter if not strong enough is a major failure, and may have to be torn down and replaced as a solution ... and the same methodology, for ensuring integrity of the bridge, gets the job done in audio ...

[fas42]

Some measurements are necessary, but not sufficient for good sound.

 

All relevant measurements are necessary and sufficient for good sound.

[jabbr]

2 hours ago, crenca said:

He is playing to the crowd like any good politician or salesman.  Pass is a good salesman -  very very $successful$ in the all too subjectivised Audiophile market. 

 

Nelson Pass is honest. Minimal BS. It is terrific that he can be open about his designs, provide his schematics for hobbyists and make money at the same time. We need more of this. He deserves every penny he makes and more. If you can solder and follow directions, you too can build one of his amps. If you can't then you can pay $$$$. Or get an old refurbished Adcom. Seems very fair to me.

[semente]

3 hours ago, crenca said:

 

On the contrary, measurements are very much related to taste.  The HP's I am presently listening (Focal Clears) are "clear" (a taste/subjective description) accurate (timbre, dynamics, etc.) and the CSD's, FR, distortion, etc. measurements all correlate to the subjective taste.  There IS a relationship after all.

 

The problem is the subjectist audiophile myth that measurements are "unrelated"...

 

I am not saying that they don't correlate, if you know how to. Many do.

 

But often equipment performance is described with taste as reference, and sometimes people's preferences don't match with good measurements and this doesn't go down well...

[DuckToller]

22 minutes ago, fas42 said:

All relevant measurements are necessary and sufficient for good sound.

Frank,

which are the measurements you find necessary and sufficient for good sound???
Tom