[B] NEED HELP - Diganosing audio differences between source components [/B] - Page 7 - AVS Forum
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post #181 of 361 Old 05-21-2012, 05:17 PM
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Originally Posted by amirm View Post

If you ignore Stereophile measurements, then what on earth are you hanging your hat on objectively?

My own measurements, for starters.

Besides, if one applies science to Stereophile, one finds that Sterophile's measurements may leave a few things to be desired, but they can be useful within the realm of their applicabiity. The subjective comments are pretty much orthogonal to the actual sonic properties of the equipment being described.

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Both Stereophile measurements and Paul Miller's have a solid place in any proper objectivist who wants to base their opinion on facts and data.

Their data is one thing, their interpretation of it is often something else.

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This anti-measurement stance on behalf of people here is really, really puzzling to me.

Amir your puzzlement likely comes from the fact that there is no anti-measurement stance here, except perhaps as a contrivance of your mind.


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I don't know how you can say you are technical, and believe in unbiased data yet want to immediately ignore anything to do with measurements.

Again Amir, the above is not actually in evidence here. What I see is people asking a very relevant and proper question - OK, what is the relevance of that measurement to sound quality?

Do you object to that question, Amir?

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I mean Stereophile is the closest thing to bible of measurements we have that is available to all. I find awful amount of useful information in looking at them. Sure, I ignore the subjective words that come before it. But the measurements are amazingly useful. And a great learning tool to compare one design to another.

IME The effectiveness of this learning tool is highly limited because you don't know how the observed differences were obtained without having schematics and knowing how to analyze them. Schematics of current high end equipment are like hen's teeth.
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post #182 of 361 Old 05-21-2012, 06:04 PM
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Originally Posted by arnyk View Post

My own measurements, for starters.

How is that an option for someone researching a product they don't yet own among a number of choices? I have expensive measurement gear yet still have great use for third party reviews of the myriad of products I can't get my hands on.

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Besides, if one applies science to Stereophile, one finds that Sterophile's measurements may leave a few things to be desired, but they can be useful within the realm of their applicabiity.

You mean as in a recent post where you looked the response of a speaker as measured by stereophile? Here it is from just a few days ago:

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Originally Posted by arnyk View Post

The preferred system was referred to as being " Listeners preferred the loudspeaker with the widest, flattest and smoothest
frequency response curves based on anechoic measurement". It's response curve is shown, and correct me if you think its wrong, but it seems to bear a strong resemblence to: http://www.stereophile.com/images/archivesart/Infin360fig3.jpg


I pulled out the link for clarity above .

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The subjective comments are pretty much orthogonal to the actual sonic properties of the equipment being described.

I agree and don't find them generally relevant or useful.

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Their data is one thing, their interpretation of it is often something else.

Not with respect to the measurement section. The descriptions there below the measurements are useful and separate from the subjective review often written by someone else.

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Amir your puzzlement likely comes from the fact that there is no anti-measurement stance here, except perhaps as a contrivance of your mind.

Hard to not take it that way when I post the measurements related to the topic at hand and you say this:
Quote:
Originally Posted by arnyk View Post

Which should be meaningless to most audiophiles because:

(a) They are just numbers

You see what I mean?

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Again Amir, the above is not actually in evidence here. What I see is people asking a very relevant and proper question - OK, what is the relevance of that measurement to sound quality?

I wish they were genuinely asking that question. Instead, they assert that there is no audible difference. If there is no audible difference, then they are not interested in relevance of measurements. They have declared them useless as you did above: "just a number." My blood pressure is just a number too .

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Do you object to that question, Amir?

No, I love the question. Because answering it would require one to have a detailed understanding of the systems under question which is usually one of the main reasons people dismiss everything else: they assume impossibilities and proceed to judge everything in that context. There is a reason I called my article: Digital Audio: The Possible and Impossible. I am at peace if we have moved passed the impossibilities and are then discussing the degree to which they are possible.

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IME The effectiveness of this learning tool is highly limited because you don't know how the observed differences were obtained without having schematics and knowing how to analyze them. Schematics of current high end equipment are like hen's teeth.

In the above speaker measurement posted, you were trying to say you knew the speaker model/brand just from its measurements in stereophile. Clearly it was not highly limited in that way. I agree that it does take a lot of knowledge to understand what to do with the said measurements. I rather have information that I can't yet understand than not have it at all .

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post #183 of 361 Old 05-22-2012, 04:58 AM
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Quote:
Originally Posted by amirm View Post


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Originally Posted by army View Post

Their data is one thing, their interpretation of it is often something else.

Not with respect to the measurement section. The descriptions there below the measurements are useful and separate from the subjective review often written by someone else.

Amir, I see that the evidence of your worship of numbers for the sake of numbers and your inability or lack of willingness to actually personally execute proper subjective or objective tests is now all around around us. You and JA appear to be twins separated at birth as related to interpretation of objective test results and subjective tests.

JA gets points for actually doing a lot of good work in the lab.

IMO it is a very self-serving for someone who sells equipment either directly or indirectly to put numbers on a high pedestal and instruct people how to worship them mindlessly.

Hence the phrase "numbers for the sake of numbers". The sooner we get influential people to move away from the worship of numbers for the sake of numbers and seek actual audible improvement, the sooner people raise audio back to where it belongs. I regret to see that Dolby labs is now on the "numbers for the sake of numbers" bandwagon:

http://www.dolby.com/uploadedFiles/A...rmance.PDF.pdf


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Hard to not take it that way when I post the measurements related to the topic at hand and you say this:

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Originally Posted by arny View Post

Which should be meaningless to most audiophiles because:

(a) They are just numbers

You see what I mean?

I see no effective rebuttal on your part, Amir. your post is just a joke!

We live in an time when we can measure just about every known effect, electrical or acoustical, way down orders of magnitude under the noise. Without relevant explanation and interpretation, objective test result numbers are indeed just numbers.

If you wish to deny that Amir, it would appear that it is your credibility that suffers.

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Originally Posted by amir View Post

Quote:
Originally Posted by arny View Post

Again Amir, the above is not actually in evidence here. What I see is people asking a very relevant and proper question - OK, what is the relevance of that measurement to sound quality?

I wish they were genuinely asking that question.

Prove they aren't!

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Originally Posted by amir View Post

Instead, they assert that there is no audible difference.

Is it an assertion or is it a reasonble conclusion based on all available evidence? In every case it is the responsibility of the one who claims that an audible difference exists to provide reliable evidence.

Trouble is, so many of the people who want to mint money based on questionable claims of audible improvements (not mere differences but worthwhile improvements!) kind of run out of gas in the science department.




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If there is no audible difference, then they are not interested in relevance of measurements. They have declared them useless as you did above: "just a number." My blood pressure is just a number too .

Amir, apparently I haven't raised your blood pressure to the point where you actually stand up from the chair in front of your computer and actually do your homework. In fact, there seems to be no evidence that you will leave the world of text editing and composing and change up the programs you run at the same computer and do relevant blind testing.

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Originally Posted by amir View Post

No, I love the question. Because answering it would require one to have a detailed understanding of the systems under question which is usually one of the main reasons people dismiss everything else: they assume impossibilities and proceed to judge everything in that context.

The most frequent impossibility that we see around here is where people assume that impossible audible differences exist.

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There is a reason I called my article: Digital Audio: The Possible and Impossible. I am at peace if we have moved passed the impossibilities and are then discussing the degree to which they are possible.

Amir, that little piece of liturgy from the Church of the Acension of Jitter lacks credibility.

Quote:


In the above speaker measurement posted, you were trying to say you knew the speaker model/brand just from its measurements in stereophile.

As in unfortunately very usual Amir, you have again shown that you cannot grasp what on the face of it seems to be a pretty simple post. While you have just libelously denied it, I have personally listened to both of the speakers I discussed on numerous occasions. I referred to numerous articles describing the audible failing of the L100 and objective tests and proposed, implemented and tested solutions for them.

Those truths would appear to mean nothing to you, Amir. Nothing!

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post #184 of 361 Old 05-22-2012, 05:21 AM
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Originally Posted by Arnyk View Post

Amir, that little piece of liturgy from the Church of the Acension of Jitter lacks credibility.

LOL

That's funny Arny
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post #185 of 361 Old 05-22-2012, 06:50 AM
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Originally Posted by Rutgar View Post

^^^

All I can say to you Arnie, is that if all of your methods of testing have shown all gear sounds the same, then your methods are most obviously very flawed.

^^^

Occam's razor.

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post #186 of 361 Old 05-22-2012, 08:05 AM
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Quote:
Originally Posted by arnyk View Post

Where do you get the idea that "All of your methods of testing have shown all gear sounds the same".

What I said was:

"Audible differences between audio gear happens a lot less often than is reported by our less careful friends"

Arnie, if I misunderstand your position, then I apologize.

As Amir, I would be interested in knowing which gear your testing showed audible differences.

- Rutgar


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post #187 of 361 Old 05-22-2012, 08:37 AM
 
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Originally Posted by Rutgar View Post

Arnie, if I misunderstand your position, then I apologize.

Will you also apologize for misjudging someone? http://www.avsforum.com/avs-vb/showp...&postcount=172
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post #188 of 361 Old 05-22-2012, 08:45 AM
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Originally Posted by arnyk View Post

Amir, I see that the evidence of your worship of numbers for the sake of numbers and your inability or lack of willingness to actually personally execute proper subjective or objective tests is now all around around us. You and JA appear to be twins separated at birth as related to interpretation of objective test results and subjective tests.

Well, looks like you don't need my help to prove your anti-measurement stance .

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JA gets points for actually doing a lot of good work in the lab.

Well, it is that "good work" that I am trying to get folks to listen to.

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IMO it is a very self-serving for someone who sells equipment either directly or indirectly to put numbers on a high pedestal and instruct people how to worship them mindlessly.

I am an information driven guy. Measurements are data if you understand how to interpret them. I wrote my article explaining how to do that and what they mean. I do the same here. My very first post here warned OP to not necessary go by the numbers:
Quote:
Originally Posted by amirm View Post

Both optical and HDMI tend to do worse in this regard than coax/S/PDIF and at any rate, will show differences in performance. That measured difference doesn't automatically result in audible difference.

I hope you appreciate that the inference in the other direction is sweeping major performance differences under the rug. A digital system is brought to its knees with distortion products that are 20 to 40 db better than it can do. And for what reason? It is not for money because another jack on the same equipment doesn't have this problem.

I think ultimately our goals in this area is different. Mine is to aspire to find the best, yours appears to be how bad we can make it when people cry uncle in listening tests. And to top that, you lack the listening tests that show that. So then you resort to an assumption that it is all good. OP can't have heard a difference. He must be mistaken as the song goes.

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Hence the phrase "numbers for the sake of numbers". The sooner we get influential people to move away from the worship of numbers for the sake of numbers and seek actual audible improvement, the sooner people raise audio back to where it belongs. I regret to see that Dolby labs is now on the "numbers for the sake of numbers" bandwagon:

http://www.dolby.com/uploadedFiles/A...rmance.PDF.pdf

That's because they understand that lossy compression when limited to 640 Kbps as it is in Blu-ray for multi-channel audio, ultimately has its limits of performance. Of note, they give away TrueHD to equipment makers who already have a Dolby license so it is not a source of new revenue for them anyway. I am puzzled though that you put Dolby of all companies down this way. Here is what you said in our last conversation about jitter regarding the company:

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Originally Posted by arnyk View Post

Amir, you've been challenged repeatedly to come up with just one proper listening test that we could compare to say the tests done by Dolby (what would they know about audio? ;-) ) that basically say "no problemo".

So when saying jitter is not as important they know something about audio but when they advocate lossless audio, they are worshiping useless numbers? Isn't it better to simply discuss the data instead of the person/entity behind them?

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We live in an time when we can measure just about every known effect, electrical or acoustical, way down orders of magnitude under the noise. Without relevant explanation and interpretation, objective test result numbers are indeed just numbers.

Until you know enough about the science to put them in context as research does in the case of distortion levels as I shown in this graph and many others:



So all of a sudden numbers aren't just numbers. In this case, we see that we can demonstrate that distortion levels in a digital system are above threshold of hearing which itself is gathered from listening tests. You ask if I like correlating measurements with audio quality. Well, here it is . But folks don't like such inconvenient truths. It is much better to assume it is all inaudible. I am good with that if we are talking about general public. I absolutely am. They do not and should not care. But for the select few who spend time sifting through these arguments to learn something about audio, dismissing measurements as "just numbers" is short changing them. Let's explain the science as we know it and then hope that a) they learn something and b) they go and conduct their own audibility test as OP here has done.

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Trouble is, so many of the people who want to mint money based on questionable claims of audible improvements (not mere differences but worthwhile improvements!) kind of run out of gas in the science department.

That continues to be the difference between us as Terry said in his post: "It's funny how hard *we* can go to maintain our rightness, and how quickly that line is crossed where we no longer wish to learn (despite our objections to the contrary) where we fight tooth and nail...usually because we know our position is so tenuous that the slightest 'loss' means the whole game is over.

FFS, Amir has sat here page after page and SHOWN how, and under what possible conditions jitter may be audible.

Hey, if it were a cable debate, and we showed with maths and sims that there could not possibly be a difference, well that would have proved it no?

So why the **** in an 'argument' where the shoe is on the other foot does it suddenly become irrelevant what the science says??

My take on what the fear might be is the worry of what might happen if we concede a point of argument. The 'other side' will drive a frickin lorry thru the door if we do."


Science needs to be about the science and not the individual or campaigns such as what you are advocating. If someone wants to know if there are differences in digital transports, we need o be able to convey that without fear that someone might run with it and say some audiophile cable is better than another. Censoring this conversation with the talk of measurements being "just numbers" and ignoring authoritative research into the topic is just not right in my book.

Anyway, we are getting argumentative again . Since you are a man of listening tests, I am hoping your next post will outline the tests you have run that showed audible difference. I am sure you have documented them elsewhere so all you have to do is provide us with a link. Would you mind doing that? Thanks in advance.

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post #189 of 361 Old 05-22-2012, 10:00 AM
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Arnie, if I misunderstand your position, then I apologize.

You definitely misunderstand my position, and I accept your apology.
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post #190 of 361 Old 05-22-2012, 12:53 PM
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...Until you know enough about the science to put them in context as research does in the case of distortion levels as I shown in this graph and many others:



So all of a sudden numbers aren't just numbers.

It is all about context. The error in the above presentation is the naive belief that the audibility of noise during music playback is limited only by the threshold of hearing of the human ear.

I've presented the reasons why the above chart falls well short of telling the whole story here many times. No need for me to repeat myself again and again to the same deaf ears.

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In this case, we see that we can demonstrate that distortion levels in a digital system are above threshold of hearing which itself is gathered from listening tests.

The above paragraph demonstrates a critical lack of knowledge about digital audio. There is no distortion in the digital domain. I've identified the true nature of this situation on this forum many times. Again I feel no need to repeat myself again and again to the same deaf ears.
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post #191 of 361 Old 05-22-2012, 01:15 PM
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It is all about context. The error in the above presentation is the naive belief that the audibility of noise during music playback is limited only by the threshold of hearing of the human ear.

It is naive to think you can control what is "music." Music can be anything it wants, including inconvenient signals that don't mask distortion. If that were not the case, then 128 K MP3s would sound perfect and generate the same fidelity regardless of input. So no, the author is not naive at all. He is striving for a transparent reproduction channel that does not have restrictions on what you can feed it.

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The above paragraph demonstrates a critical lack of knowledge about digital audio. There is no distortion in the digital domain. I've identified the true nature of this situation on this forum many times. Again I feel no need to repeat myself again and again to the same deaf ears.

No one was talking about distortion in "digital domain." I said a digital *system*. A system that people care about has analog audio coming out of it, not starring at the digital bits inside of computer .

BTW, are we not going to see documented results of your listening tests where differences were found? It is fine if the answer is no. Just want to know one way or the other please .

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post #192 of 361 Old 05-22-2012, 01:46 PM
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Now that I see the graph I don't understand what does it mean that assumption that full scale signal can go up to 120dB at the listening position?

What about if the signal is just only 90dB, the usual listening level at the listening position in most cases?
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post #193 of 361 Old 05-22-2012, 03:03 PM
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Originally Posted by JorgeLopez11 View Post

Now that I see the graph I don't understand what does it mean that assumption that full scale signal can go up to 120dB at the listening position?

As they say, "there is an argumentative thread for that!" http://www.avsforum.com/avs-vb/showt...5#post21775025. I have the research papers cited there extensively.

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What about if the signal is just only 90dB, the usual listening level at the listening position in most cases?

Most cases? How about the rest of the cases? Where did 90 come from anyway? What about 85? Or 81? Where do we stop and why?

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post #194 of 361 Old 05-22-2012, 03:24 PM
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Originally Posted by amirm View Post

Most cases? How about the rest of the cases? Where did 90 come from anyway? What about 85? Or 81? Where do we stop and why?

This might be a good place to start:

http://www.dangerousdecibels.org/edu...me-guidelines/
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post #195 of 361 Old 05-22-2012, 03:36 PM
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This might be a good place to start:

http://www.dangerousdecibels.org/edu...me-guidelines/

Actually it wouldn't be a good start. Safety standards are not what we are talking about here. You see that first column saying continuous dB in the above graph? Music is not a single tone/noise lasting for minutes or hours continuously that way. We are talking about dynamic range that can shoot up there for moments in time.

THX standard for dynamic range is 105 dB which is in the red region of that graph. You think they would recommend something that would make you go deaf that way?

Really guys, these things have been researched and published. I showed it all in that thread. The statements do not come from random people who don't know what they are talking about. Let's not put simplistic defenses like this forward. Take a minute and read the data. I have quoted the papers extensively so you don't even need to buy the papers if you don't want.

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post #196 of 361 Old 05-22-2012, 06:12 PM
 
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Originally Posted by amirm View Post

music can be anything it wants, including inconvenient signals that don't mask distortion.

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music is not a single tone/noise lasting for minutes or hours continuously that way.

LOL!
I guess you've never listened to pipe organ music.
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post #197 of 361 Old 05-22-2012, 06:37 PM
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Originally Posted by amirm View Post

As they say, "there is an argumentative thread for that!" http://www.avsforum.com/avs-vb/showt...5#post21775025. I have the research papers cited there extensively.

Most cases? How about the rest of the cases? Where did 90 come from anyway? What about 85? Or 81? Where do we stop and why?

I'll take a look Amirm. Thanks.

Regarding the SPL, well, most people I know sits every afternoon in a favourite seat and listen to their audio gear for two or three hours. I think it is a reasonable guess they do not play anything louder than 90dB on a continous basis. In fact I also do that.

What about you Amirm. Do you listen your CDs at 120dB for two hours?
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post #198 of 361 Old 05-22-2012, 07:11 PM
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The three lower traces of that graph make no sense whatsoever. What does it mean to plot audibility of white noise vs. frequency? By definition, white noise has a power spectral density (Watts/Hz) that's independent of frequency. So if you wanted to figure out the noise power at, say, 1kHz, what would it be? It's zero. That's because the noise power is the integral from f1 to f2 of the Watts/Hz as a function of frequency, where f1 is the lowest frequency under consideration, and f2 is the highest. At a single frequency, the interval is of length zero, so the integral evaluates to zero Watts (zero area under the curve when f1=f2). If you want a non-zero number, you have to pick some bandwidth around the frequency under consideration, but that makes no sense either, as the result you get gives power proportional to bandwidth. That only raises other questions, such as what bandwidth do you choose, and why? The only thing that makes any sense at all is integrating the spectral density (or perhaps a frequency-weighted version of it) over the entire audible band to give a single number in Watts (or RMS Volts), and examine the threshold of audibility of that one single number (not a function of frequency!) when converted to dB SPL.

So either the person who came up with that graph didn't have any understanding of noise analysis whatsoever, or it was mislabeled and is really something else (who knows what?).
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post #199 of 361 Old 05-22-2012, 07:44 PM
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BTW, here is a book showing what the ideal max SNR of a digital system of n bits with triangular PDF dither. It is:

SNR = 6.02n - 3.0 dB

So, for 16 bits, it is 93.3 dB. That allows a sine wave of 93.3 dB average SPL when the noise is at 0 dB SPL. A sine wave has a peak SPL 3 dB higher (because of the peak-to-RMS ratio of a sine wave).

Bottom line, 96.3 dB peak SPL (or 93.3 dB average SPL) for triangular PDF noise at 0 dB average SPL.
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Originally Posted by rock_bottom View Post

The three lower traces of that graph make no sense whatsoever. What does it mean to plot audibility of white noise vs. frequency? By definition, white noise has a power spectral density (Watts/Hz) that's independent of frequency. So if you wanted to figure out the noise power at, say, 1kHz, what would it be? It's zero. That's because the noise power is the integral from f1 to f2 of the Watts/Hz as a function of frequency, where f1 is the lowest frequency under consideration, and f2 is the highest. At a single frequency, the interval is of length zero, so the integral evaluates to zero Watts (zero area under the curve when f1=f2). If you want a non-zero number, you have to pick some bandwidth around the frequency under consideration, but that makes no sense either, as the result you get gives power proportional to bandwidth. That only raises other questions, such as what bandwidth do you choose, and why? The only thing that makes any sense at all is integrating the spectral density (or perhaps a frequency-weighted version of it) over the entire audible band to give a single number in Watts (or RMS Volts), and examine the threshold of audibility of that one single number (not a function of frequency!) when converted to dB SPL.

The author of that paper has written not one, but two other papers for the Journal Audio Engineering Society that are entirely about how to model the perceptual/audible effect of those lines so that they can be compared to the tones used in determining the threshold of hearing. The work is quite detailed starting at where you are and then getting into ear's response using ERB analysis to first modify the audibility of the noise and then comparing to threshold of hearing. I am of course hugely oversimplifying.

Quote:
So either the person who came up with that graph didn't have any understanding of noise analysis whatsoever, or it was mislabeled and is really something else (who knows what?).

Who knows what? I do . I have read the papers. He is not guilty of either.
The papers are very enjoyable. I suggest downloading and reading instead of spending time here .

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post #201 of 361 Old 05-23-2012, 06:24 AM
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Originally Posted by amirm View Post

The work is quite detailed starting at where you are and then getting into ear's response using ERB analysis to first modify the audibility of the noise and then comparing to threshold of hearing. I am of course hugely oversimplifying.

Okay, that makes more sense. It helps to actually describe what it is being plotted when posting a plot, as opposed to just throwing it out there. In this case the caption of the plot just does not begin to describe how the lower three curves were obtained.

I've grabbed the Fielder papers and will look at them when I get a chance.
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post #202 of 361 Old 05-23-2012, 06:40 AM
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Originally Posted by JorgeLopez11 View Post

I'll take a look Amirm. Thanks.

Regarding the SPL, well, most people I know sits every afternoon in a favourite seat and listen to their audio gear for two or three hours. I think it is a reasonable guess they do not play anything louder than 90dB on a continous basis. In fact I also do that.

What about you Amirm. Do you listen your CDs at 120dB for two hours?

..that would explain why Amir doesn't seem to want to do any ABXing himself. If he made a habit of listening @ 120 dB, he wouldn't be able to hear the difference between just about anything! ;-)

When people talk about listening to 120 dB sounds, and then hearing small sounds at the given threshold of hearing, they are subtly telling us about their lack of understanding about hearing. ;-)

Even 90 dB sounds can cause threshold shifts, which is a nice way of saying that the every act of listening to music can at least temporarily limit your ability to hear subtle differences.

It is well known that the ideal SPL for hearing differences is around 80-85 dB.

The actual instantaneous dynamic range of the human ear is about 70 dB at best, and less under many practical circumstances. One indication of this is the fact of audiophile preference for listening to vinyl, other analog sources, and digital recordings sourced from legacy analog sources. None of these sources can possibly have more than about 70 dB dynamic range.
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Originally Posted by rock_bottom View Post

Okay, that makes more sense. It helps to actually describe what it is being plotted when posting a plot, as opposed to just throwing it out there. In this case the caption of the plot just does not begin to describe how the lower three curves were obtained.

I've grabbed the Fielder papers and will look at them when I get a chance.

Please be aware of the age of Fielder's papers, the commercial failure of technologies that were based on them, and the rebuttal for the false claims contained therein that were probably innocent enough when they were made.
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Originally Posted by amirm View Post

Actually it wouldn't be a good start.

Actually, it would be unless your goal is to ruin your hearing.

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Safety standards are not what we are talking about here.

This is IMO utterly irresponsible! We're supposed to physically hurt ourselves while enjoying our hobby?

The worst thing about OSHA standards is that is well known that they are too broad to provide ear protection and maintain hearing at audiophile levels.

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You see that first column saying continuous dB in the above graph? Music is not a single tone/noise lasting for minutes or hours continuously that way.

Amir, aren't you contradicting yourself when you just said:

"It is naive to think you can control what is "music." Music can be anything it wants, including inconvenient signals that don't mask distortion." LOL!

Oh, I get it, Amir. You can forget what you just said if it is inconvenient for your current argument!

Getting away from Amir's convenient memory and back on track...

Besides pipe organs, what about all of those highly compressed recordings that people complain about so much?

Quote:


We are talking about dynamic range that can shoot up there for moments in time.

Or go there and stay there for the duration of a CD with 2 second breaks between the tracks.

Amir what was it that you were saying about not cherry-picking recordings?

Quote:


THX standard for dynamic range is 105 dB which is in the red region of that graph. You think they would recommend something that would make you go deaf that way?

THX is not well known as a public health agency...



Quote:


Really guys, these things have been researched and published.

But some of it is old, some of it has been effectively rebutted, and some of it has a very narrow intent.

Quote:


I showed it all in that thread.

But Amir you have been effectively rebutted and you continue to act like there was only one side to the story - yours!

Quote:


The statements do not come from random people who don't know what they are talking about.

Technology and human understanding march on.

Quote:


Let's not put simplistic defenses like this forward.

Why not? You ignore all other thoughts!

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Take a minute and read the data. I have quoted the papers extensively so you don't even need to buy the papers if you don't want.

Yes Amir, you just rehash and rehash the same outdated information over and over again.
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Originally Posted by arnyk View Post

Please be aware of the age of Fielder's papers, the commercial failure of technologies that were based on them, and the rebuttal for the false claims contained therein that were probably innocent enough when they were made.

I have the AES CD set, and the one article I"m looking at is 1995. By rebuttals, do you mean in the AES Journal or elsewhere?

I've "tuned out" much of the discussion but was sucked in by ignore list leakage .

I can see how noise in a 16-bit system might be audible in a recording like Tom Danley's fireworks track, but I don't know of any musical material that even comes close to that kind of peak-to-RMS ratio.
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Originally Posted by rock_bottom View Post

I have the AES CD set, and the one article I"m looking at is 1995. By rebuttals, do you mean in the AES Journal or elsewhere?

I have the AES CD set though about 2004, and know of no formal rebuttals.

I've pointed out the effects of later understandings here and other forums like Hydrogen Audio. HA has some real industry technical heavyweights posting there.

For example, the Fielder plot that Amir has posted here about 463 times does not seem to show the benefits of using modern noise shaping during recording. It does not show the effects of real-world ambient noise in both the recording and the playback space. It ignores the technical problems with associated equipment like power amps and speakers. It ignores the effects of Temporary Threshold Shift (TTS) on the human ear.

There are documents from international standards organizations such as ITU BS 1116 that detail the requirements for a critical listening environment that have far less dynamic range.

That's 5 heavy hits. ;-)


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I can see how noise in a 16-bit system might be audible in a recording like Tom Danley's fireworks track, but I don't know of any musical material that even comes close to that kind of peak-to-RMS ratio.

IME fireworks shows have too much background noise to be real killers when it comes to dynamic range. I'd bet you that any audible noise you hear while playing it is on the tracks, and well above the media's noise floor.
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Originally Posted by arnyk View Post

Please be aware of the age of Fielder's papers, the commercial failure of technologies that were based on them, and the rebuttal for the false claims contained therein that were probably innocent enough when they were made.

Commercial failures? Someone measures the dynamic range of live music halls and how quiet listening rooms are relative to it, and their work is no good because of "commercial failures of technologies that were based on them?" What exactly are those technologies? Here is the man's resume: http://www.linkedin.com/profile/view...file_name_link

"Senior Director
Dolby Labs Inc
Currently holds this position

Treasurer
Audio Engineering Society
Nonprofit; 11-50 employees; Music industry
2005 – Present (7 years)

Senior Director
Dolby Laboratories
Public Company; 1001-5000 employees; DLB; Entertainment industry
1984 – Present (28 years)


Research Member
Ampex
Public Company; 1001-5000 employees; AMPX; Computer Hardware industry
September 1977 – March 1984 (6 years 7 months)

Education

University of California, Los Angeles
MSEE, acoustics, filter theory
1974 – 1977

Activities and Societies: Audio Engineering Society
California Institute of Technology
BSEE, electronics-audio technology
1969 – 1974

Additional Information

Groups and Associations:
Audio Engineering Society
IEEE
Acoustical Society of America
SMPTE

Honors and Awards:
Fellow of the Audio Engineering Society 1992
Senior Member of the IEEE"


What about this kind of resume points to someone who is a failure at his research? Ampex may be gone but they provided us with incredible amount of technology that is used even today in many products/standards. They are to video world what Xerox is to GUI development in computers. And Dolby? It must be news to their investors that they have long time senior employees/researchers who apparently not able to determine the dynamic range of content their company monetizes to encode. And are failures at any technology they have touched.

Disagree with what the man has to say but please, don't go after his accomplishments. He deserves more than that. The industry recognizes that. You should too. Let's not turn into national inquirer headline and have a professional discussion based on merits of the topic.

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Originally Posted by amirm View Post

Commercial failures? Someone measures the dynamic range of live music halls and how quiet listening rooms are relative to it,

And as I have pointed out repeatedly and without effective rebuttal, interpreted the data he found incorrectly.

Quote:


and their work is no good because of "commercial failures of technologies that were based on them?" What exactly are those technologies?

HDCD
DVD-A
SACD

All are based on the idea that Redbook CD has inadequate dynamic range for reproducing music. None went mainstream.
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Originally Posted by arnyk View Post

And as I have pointed out repeatedly and without effective rebuttal, interpreted the data he found incorrectly.

I debated this work with you and in every instance your counter was incorrect. You said that music never gets that loud. He provided actual measurements of concert halls that was way, way higher than what you claimed. You then said no room is very quiet and pointed to meter measurements of how loud noise is in your room. His papers showed that your analysis was completely wrong because the ear has different sensitivity for each frequency of noise. He then showed measurements of rooms that are absolutely quiet based on that perceptual model. As in this thread, you also made a number of other factual errors regarding your read of BBC papers and such. I think if there ever was a discussion between us where you had no argument left, that was it!

Quote:


HDCD
DVD-A
SACD

He is responsible for these formats? Really? Talk about rewriting history. How about DVD and Blu-ray which actually use Dolby technology? Both support higher dynamic range than the CD, going as far as 24 bits. They are failures too?

Quote:


All are based on the idea that Redbook CD has inadequate dynamic range for reproducing music. None went mainstream.

I guess you have never sat in a theater with better than 96 db dynamic range. Oh, I forgot this is your setup:

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Originally Posted by arnyk View Post

I don't even own an AVR. If I bought 2 $1k AVRs, I absolutely, positively wouldn't be able to pay the taxes on my house this year. My $99 Blu Ray player runs through my TV set and my DAC runs off the coax output of the same. The DAC drives a $79 Sherwood receiver which drives 2 BA CR9s (street value maybe $100) and a obtained-used Paradigm subwoofer.

I suggest going to someone's dedicated theater and listen to the enjoyment and realism that high dynamic range brings.

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post #210 of 361 Old 05-23-2012, 03:15 PM
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Quote:
Originally Posted by amirm View Post

I debated this work with you and in every instance your counter was incorrect. You said that music never gets that loud. He provided actual measurements of concert halls that was way, way higher than what you claimed. You then said no room is very quiet and pointed to meter measurements of how loud noise is in your room. His papers showed that your analysis was completely wrong because the ear has different sensitivity for each frequency of noise. He then showed measurements of rooms that are absolutely quiet based on that perceptual model. As in this thread, you also made a number of other factual errors regarding your read of BBC papers and such. I think if there ever was a discussion between us where you had no argument left, that was it!


He is responsible for these formats? Really? Talk about rewriting history. How about DVD and Blu-ray which actually use Dolby technology? Both support higher dynamic range than the CD, going as far as 24 bits. They are failures too?


I guess you have never sat in a theater with better than 96 db dynamic range. Oh, I forgot this is your setup:



I suggest going to someone's dedicated theater and listen to the enjoyment and realism that high dynamic range brings.

You have a very disrespectful and condescending tone. I am not saying just in this post, but in general. That is why you are not liked in these forums and get attacked by so many different posters.

And quoting from your arny_insults.txt file in your reply will not change that.
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