Debate Thread: Scott's Hi-res Audio Test - Page 26 - AVS Forum
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post #751 of 2920 Old 06-19-2014, 01:44 PM
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Originally Posted by Audionut11 View Post
You can't ABX the happiness of the people on the slippery slide, so I reject your conclusion.
Says who? Experts? Have they considered the happiness frequency to determine whether it will be masked? How happy do they need to be to be measurably happy? Let me explain it all.
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post #752 of 2920 Old 06-19-2014, 01:58 PM
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Originally Posted by arnyk View Post
The equivalent of amplitude modulation in FM is known as the Modulation Index and it is twice the amplitude of the sideband times the modulation frequency for small modulation indices. Modulation indices are usually given as decimal numbers.

In the actual calculation I take the amplitude in dB, divide it by 20 and then raise 10 to that power to get a numeric modulation amplitude. This is just converting signal amplitude in dBs to signal amplitude as a fraction of the carrier amplitude. The modulation index for the first sideband pair of a lightly modulated FM signal (or narrowband FM) or FM with a Modulation Index of << 1 is half the signal amplitude as a fraction of the carrier amplitude.
But isn't this an indirect method by measuring the FM effect on audio? Isn't what's really happening is jitter induced into the audio from instability in the audio clock derived from the HDMI clock? Could one not just look at a FFT of the difference in timing between the jittery clock and a stable one, which in effect would be an error signal in a PLL control loop?
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post #753 of 2920 Old 06-19-2014, 02:58 PM - Thread Starter
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Originally Posted by TVOD View Post
But isn't this an indirect method by measuring the FM effect on audio? Isn't what's really happening is jitter induced into the audio from instability in the audio clock derived from the HDMI clock? Could one not just look at a FFT of the difference in timing between the jittery clock and a stable one, which in effect would be an error signal in a PLL control loop?
You could do that if you can tap the output of the PLL. Many dacs have internal PLLs that clean incoming jitter as I showed before:



Without access to PLL output, you would be forced to measure the input clock to the PLL which overstate the amount of jitter.

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post #754 of 2920 Old 06-19-2014, 03:01 PM
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Originally Posted by Audionut11 View Post
You can't ABX the happiness of the people on the slippery slide, so I reject your conclusion.



What annoys m the most, is that the participants of this thread are very knowledgeable people, certainly, more knowledgeable on these subjects then I. But there is never any actual useful outcome to the threads. FFS, it would be nice to follow one of these threads one day, and actually learn something, other then witty remarks, or how to derail a thread, and make it go around in circles, without producing a useful outcome.

This entire section of the forums should be renamed to, "How to sidetrack useful outcomes"!
I think the problem is that both sides have weak scientific arguments, at best, so in the end it boils down to preference. Some believe - correctly, I think - that ultimately high end or well engineered gear and high resolution music will sound better, and some cannot hear any difference, and believe it's an elaborate hoax, a marketing ploy, to dupe people into spending more money.

What I am confused about is the amount of passion, arrogance and plain nastyness of the so-called "objectivist" side. At the end of the day, there's real value to be had from SACD/DVD-A/Audio BluRay formats, which is multichannel music. It doesn't even need to cost more - in fact, I never paid more for such media than I ever paid for an average plain old CD.

Considering that they've insulated themselves from the need to spend money on high-end gear, and that high resolution music is no more than a small, niche market, I don't quite understand where the energy for the debate comes from. It'a a fruitless endeavor.
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post #755 of 2920 Old 06-19-2014, 03:28 PM
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Originally Posted by amirm View Post
You could do that if you can tap the output of the PLL. Many dacs have internal PLLs that clean incoming jitter as I showed before
Sorry for not going through every page

So in the chart the jitter rejection at around 0db means the clock at that frequency essentially follows the input clock, while lower values average out the error? To create this chart, is jitter induced at the various frequencies and then measured (which might explain the discrete points)?

I'm a bit surprised to see the jitter rather even across frequencies. I would have expected a roll-off with frequency.
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post #756 of 2920 Old 06-19-2014, 03:42 PM
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Originally Posted by symphara View Post
What I am confused about is the amount of passion, arrogance and plain nastyness of the so-called "objectivist" side.
Such is life with master debaters.
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post #757 of 2920 Old 06-19-2014, 04:18 PM
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Originally Posted by TVOD View Post
But isn't this an indirect method by measuring the FM effect on audio?
It is how it is done. Most audio measurements are to some degree, indirect.


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Originally Posted by TVOD View Post
Isn't what's really happening is jitter induced into the audio from instability in the audio clock derived from the HDMI clock?
There is no such thing as a HDMI clock. Check the HDMI interface specs. No clock line, no clock signal, just digital data. Just like S/PDIF and many other digital audio interfaces. The clock signal is intermixed with the data.

However, this discussion is about jitter in general. These are general truths - true for LP playback, true for OTA signals, true for analog tape, true for CD players, true for lots of things.

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Originally Posted by TVOD View Post
Could one not just look at a FFT of the difference in timing between the jittery clock and a stable one, which in effect would be an error signal in a PLL control loop?
A FFT analysis of a clock signal should be based on a stable clock. There is no need for taking differences.
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post #758 of 2920 Old 06-19-2014, 04:30 PM
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Originally Posted by symphara View Post
I think the problem is that both sides have weak scientific arguments, at best, so in the end it boils down to preference.
Are you sure that you are qualified to judge the strengths of scientific arguments? I've got my doubts!

But lets say that the scientific arguments are weak. It strikes me as being very unwise to resort to something as unreliable and vague as preference. Why not just suspend making any judgments until the arguments get strong enough?

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Originally Posted by symphara View Post
Some believe - correctly, I think - that ultimately high end or well engineered gear and high resolution music will sound better, and some cannot hear any difference, and believe it's an elaborate hoax, a marketing ploy, to dupe people into spending more money.
It strikes me that many of these issues can be resolved pretty quickly with some well-designed listening tests. In the end its all about sound quality, and the most relevant judge of sound quality involves human beings doing the best possible job of listening, right?


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Originally Posted by symphara View Post
What I am confused about is the amount of passion, arrogance and plain nastyness of the so-called "objectivist" side.
IMO there is plenty of passion, arrogance and just plain nastiness on both sides. Therefore your statement taken at face value suggests that you understand that passion, arrogance and just plain nastiness on the subjective side. Please explain it for us.

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At the end of the day, there's real value to be had from SACD/DVD-A/Audio BluRay formats, which is multichannel music. It doesn't even need to cost more - in fact, I never paid more for such media than I ever paid for an average plain old CD.
That's not the question at hand. The question at hand relates to the sound quality of high resolution formats. We had multichannel music for a long time without high resolution formats, didn't we?

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Originally Posted by symphara View Post
Considering that they've insulated themselves from the need to spend money on high-end gear, and that high resolution music is no more than a small, niche market, I don't quite understand where the energy for the debate comes from. It'a a fruitless endeavor.
I don't think that anybody needs to spend extra bucks on high end gear to listen to high resolution recordings any more. I think that just about every BD player and AVR does it for no extra cost. I think you pointed out (and I agree) that in general there is no extra cost any more for music and drama in high resolution formats. I think that my $99 BD player and $499 AVR handle high res formats just fine.
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post #759 of 2920 Old 06-19-2014, 04:32 PM
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Originally Posted by Audionut11 View Post
This thread was actually gaining some traction for a little while there. Somehow, it got sidetracked into a pissing contest, yet again.
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Originally Posted by Audionut11 View Post
What annoys m the most, is that the participants of this thread are very knowledgeable people, certainly, more knowledgeable on these subjects then I. But there is never any actual useful outcome to the threads. FFS, it would be nice to follow one of these threads one day, and actually learn something, other then witty remarks, or how to derail a thread, and make it go around in circles, without producing a useful outcome. This entire section of the forums should be renamed to, &quot;How to sidetrack useful outcomes&quot;!
So you were expecting educational material from a thread that's designed to bolster and protect the sales pitches already made for boutique electronics sold by the thread starter? Sorry to hear. By chance, you would get some useful data from other posters calling out the marketing hypes ever present in such threads but the core idea in threads like this carries a stench of sales tactics. If you care about learning, read the textbooks, not whitepapers published by companies selling the products or their online followup threads.
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post #760 of 2920 Old 06-19-2014, 05:05 PM
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Originally Posted by arnyk View Post
I think I get it. I'll give it a try. I kinda thought so, but you made it "official". Thanks.
Or, if it is a response to only one person, you can replace the initial quote bracket containing the posters name on subsequent response to a sentence/phrase with [QUOTE]


ps.
it doesn't work anymore.

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post #761 of 2920 Old 06-19-2014, 05:14 PM
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Originally Posted by arnyk View Post
There is no such thing as a HDMI clock. Check the HDMI interface specs. No clock line, no clock signal, just digital data.
What is the clock on pins 10 & 12 used for?

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Originally Posted by arnyk View Post
A FFT analysis of a clock signal should be based on a stable clock. There is no need for taking differences.
A bit of semantics, using a stable clock as a reference is the same thing. If one XORs the stable clock and the jittered clock 90 degrees apart with a filter and did a FFT, shouldn't that show the jitter spectrally?

I understand some of the the underlying debate is the audibility of jitter, but there was much discussion regarding HDMI. I see HDMI audio is somewhat similar to SDI embedded audio in that it's in the inactive video portion. Embedded audio is a mixed blessing, but I'll take it over dealing with 8 discrete AES stereo pairs. I really should pay more attention to these formats

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post #762 of 2920 Old 06-19-2014, 05:16 PM
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Originally Posted by CharlesJ View Post
Or, if it is a response to only one person, you can replace the initial quote bracket containing the posters name on subsequent response to a sentence/phrase with QUOTE
Yes, but when you do that, it's not formatted nicely.
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post #763 of 2920 Old 06-19-2014, 05:22 PM
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Yes, but when you do that, it's not formatted nicely.
Well, just tried it and you are right, not anymore. Used to work.

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post #764 of 2920 Old 06-19-2014, 06:22 PM - Thread Starter
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Originally Posted by arnyk View Post
There is no such thing as a HDMI clock. Check the HDMI interface specs. No clock line, no clock signal, just digital data.
Good grief Arny. Are you playing with us?



See (TDMS) clock pins at the bottom?

Maybe the "weak science" argument is right after all....

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post #765 of 2920 Old 06-19-2014, 06:35 PM - Thread Starter
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Originally Posted by arnyk View Post
It strikes me that many of these issues can be resolved pretty quickly with some well-designed listening tests. In the end its all about sound quality, and the most relevant judge of sound quality involves human beings doing the best possible job of listening, right?
Hi Arny. Putting aside the fact that the last bit reads just like a subjectivist saying "trust your ears," why is it that when I asked you if you have ever documented any such listening tests, the only one was this amplifier test:



Arriving at this conclusion:



When we discussed this earlier in this thread, it seemed that were trying our damndest to disown its results. Why would we do more work like this only to have it be dismissed?

But sure, please create more of these tests, run them and report to us how well you could hear these distortions.

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Originally Posted by arnyk View Post
I don't think that anybody needs to spend extra bucks on high end gear to listen to high resolution recordings any more. I think that just about every BD player and AVR does it for no extra cost. I think you pointed out (and I agree) that in general there is no extra cost any more for music and drama in high resolution formats. I think that my $99 BD player and $499 AVR handle high res formats just fine.
It is good that you think that Arny. The problem is, you have to demonstrate it. Sitting right here, you have no measurements of broad set of AVRs to know what they do or don't, right? How can we be so clairvoyant as to know a priori what distortion a product has? I know I am not one tenth as smart as what is required to figure that out .

Seems to me, we should put the data forward and let the chips fall where they may. You yourself said we should run listening tests above only to say in a couple of paragraph later that none is needed because we have already made up our mind even though we lack the data.

If we foreclose the conversation as you are doing, then it will look like we are hiding something. We should not be partisan as to outcome of such tests. That is the fastest way in becoming the other camp .

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post #766 of 2920 Old 06-19-2014, 06:52 PM
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See (TDMS) clock pins at the bottom?
In reading how TMDS works, there doesn't seem to be self clocking. Regardless of if it's self clocked or external, my assumption is the audio is squeezed into blanking sized blocks using the same clock as video in a similar fashion to embedded SDI. Another question I have is how source dependent the HDMI audio jitter is on these AVRs. If fed with an extremely stable source requiring minimal cable EQ, do they still introduce significant jitter from internal noise?
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post #767 of 2920 Old 06-19-2014, 06:58 PM
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Hi Arny. Putting aside the fact that the last bit reads just like a subjectivist saying "trust your ears," why is it that when I asked you if you have ever documented any such listening tests, the only one was this amplifier test:



Arriving at this conclusion:



When we discussed this earlier in this thread, it seemed that were trying our damndest to disown its results. Why would we do more work like this only to have it be dismissed?

But sure, please create more of these tests, run them and report to us how well you could hear these distortions.


It is good that you think that Arny. The problem is, you have to demonstrate it. Sitting right here, you have no measurements of broad set of AVRs to know what they do or don't, right? How can we be so clairvoyant as to know a priori what distortion a product has? I know I am not one tenth as smart as what is required to figure that out .

Seems to me, we should put the data forward and let the chips fall where they may. You yourself said we should run listening tests above only to say in a couple of paragraph later that none is needed because we have already made up our mind even though we lack the data.

If we foreclose the conversation as you are doing, then it will look like we are hiding something. We should not be partisan as to outcome of such tests. That is the fastest way in becoming the other camp .
The topic is jitter. Please stay on topic.

Thanks.
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post #768 of 2920 Old 06-19-2014, 07:09 PM
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The topic is jitter.
Or is it the thread has jitter.
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post #769 of 2920 Old 06-19-2014, 09:48 PM
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Originally Posted by symphara View Post
I think the problem is that both sides have weak scientific arguments, at best, so in the end it boils down to preference. Some believe - correctly, I think - that ultimately high end or well engineered gear and high resolution music will sound better, and some cannot hear any difference, and believe it's an elaborate hoax, a marketing ploy, to dupe people into spending more money.

Well-engineered *recordings* and *masterings* will sound better than badly engineered ones.

You left that one out. And it's the one that makes the biggest, and least controversial, difference.


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Originally Posted by symphara View Post
What I am confused about is the amount of passion, arrogance and plain nastyness of the so-called "objectivist" side. At the end of the day, there's real value to be had from SACD/DVD-A/Audio BluRay formats, which is multichannel music. It doesn't even need to cost more - in fact, I never paid more for such media than I ever paid for an average plain old CD.
Agreed about multichannel...which can't be done with S/PDIF, except as lossy versions (which can sound great too).

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post #770 of 2920 Old 06-19-2014, 10:18 PM
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Originally Posted by amirm View Post

Since this "appeal to authority" argument keeps getting made, I'll suspend reality for a few minutes and pretend that argument actually matters.

So let's go to the above Wiki and see what is there:

Argument from authority (Latin: argumentum ab auctoritate), also authoritative argument and appeal to authority, is a common form of argument which leads to a logical fallacy when misused.[1]
Thank you for breaking out of your bubble of assumed correctness. What's the term for debaters who are so greedy to be right, that they can never fathom that they are wrong?

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This is the very first sentence in the Wiki. You would think it would be quoted above but it is not.

Maybe this is why: notice the part I have highlighted in red which is key to it. You must demonstrate *misuse*. The very fact that someone quotes an authority gives you no automatic permission to make this argument. You have to demonstrate misuse. There was no misuse in showing that the who is who of people in audio have an opposing view to you all. This is normative and probative to the conversation we are having. It is the height of silliness to attempt to dismiss this nugget of information as "appeal to authority." Yes, it is appeal to authority and the proper way to do so to give credibility to the statement relative to random dude online.
While the bubble is broken, perhaps it would be of benefit, if you read the detailed explanation of your logical missteps; you know, the one citing discussion comments and rudimentary boolean logic to demonstrate misuse of "authority" and "strawman logic" to buttress your argument. Until you address those particulars, your post amounts to something less in importance than flagellation.

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We do that routinely in our everyday life. If I asked you why you are sneezing, you can say, "my doctor says I have allergies." I don't get to come back and say, "oh, appeal to authority. That doesn't mean you have allergies." That may be true but sure as heck does not give me license to use that argument when I am not a doctor and have no medical training to invalidate that statement and hence demonstrate misuse.
I'm supposed to be enlightened by this misanthropic analogy: the sneezer and confused observer? I venture to guess, given the the sloppily applied relevance to the subject at hand, the example was meant as an insult. You don't expect anyone to take this seriously.

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Don't believe me still? You see that little [1] at the end? You didn't click on that footnote, did you? Because if you had, you would see that the fundamental definition is taken from this web page: http://www.stanford.edu/~jonahw/PWR1...lFallacies.htm

We see that the reference is "student handout" for a stanford university course. Here is the start of it. Make sure you are sitting down when you read this :

Logical Fallacies
(Handout developed by Kimberly Moekle)

All of these definitions come from “Stephen’s Guide to the Logical Fallacies,” located at http://datanation.com/fallacies/index.htm, where you can find further information on all of the fallacies listed below. Stephen Downes is a Senior Researcher for the National Research Council of Canada, where he currently works as an “information architect,” and has become a leading voice in the areas of learning objects and metadata, as well as the emerging field of weblogs in education and content syndication.


Oh my! There is an "appeal to authority" right at the start! We are supposed to agree with this definition because Mr. Downes told us? And that he is an "information architect?" A "leading voice?" All appeal to authority and then some!

Why is it OK to have that appeal? Because there is no misuse. It is proper to say the source of your information and credentials of the authors. It lends support to what is being said as being true.
Unlike your incorrect use of citation, the Wiki article demonstrates proper usage. Now, its more apparent what can be accomplished when logic is used properly and deepens the understanding of your failure.

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This is how we lose all credibility in the eyes of the other camp guys. We ask people to suspend reality and live in this imaginary world where we can dismiss any technical references that oppose our religion in audio as "appeal to authority this," and "strawman that" when we don't even know the real meaning of these terms. Worse yet, every time we use them, it shows that we have no technical argument to make. You are destroying whatever credibility we have in our position.
LOL! And your bias is made evident... Thank you for illuminating one of your motivations. This camp defeating that camp. Sorry son, but I'm not an audio jihadist. I can't help you further your mission. Whatever it might be...

I suggest that you continue writing your amateurish tabloid articles in aid of your mission. You don't seem responsible enough to handle two-way forum discussions in a professional, unbiased manner.
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post #771 of 2920 Old 06-19-2014, 10:33 PM - Thread Starter
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Originally Posted by TVOD View Post
In reading how TMDS works, there doesn't seem to be self clocking. Regardless of if it's self clocked or external, my assumption is the audio is squeezed into blanking sized blocks using the same clock as video in a similar fashion to embedded SDI. Another question I have is how source dependent the HDMI audio jitter is on these AVRs. If fed with an extremely stable source requiring minimal cable EQ, do they still introduce significant jitter from internal noise?
HDMI definitely has an explicit clock. Indeed, that is one of the reasons HDMI is not reliable over long distances. With clock cycle of just ~4ns, slightest length difference between the wire pairs can cause the eye to close, causing data loss.

Back to your question, my testing shows that most of the ills of HDMI are self induced in the receiver. Here is a composite sampling:



The source is the same in all cases, driving the display at the same resolution and scan rate. Yet each device is exhibiting different set of noise/modulation/jitter characteristics. It is for this reason that I say the implementations suffer from poor engineering. Good circuit design hygiene would keep a lot of that "crud" out of the sensitive DAC circuits.

Some distortion/noise does bleed through from the source due to lack of electrical isolation with HDMI. Here is a composite of a number of HDMI AVRs/processors yet again showing this problem:



The highlighted area is common to all which no doubt is coming from my laptop source device. Different source devices will likely show different correlated noise.

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post #772 of 2920 Old 06-19-2014, 11:17 PM
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I suggest that you continue writing your amateurish tabloid articles in aid of your mission. You don't seem responsible enough to handle two-way forum discussions in a professional, unbiased manner.
Your post could be taken as an insult to many highly intelligent people who simply do not have a mastery of the English language. Following MLA citation (or whatever format is accepted now), using proper punctuation, not bastardizing the English language, or using flowery language are a all nice and generally appreciated, but it is not required to convey a message. Someone could lack the communication skills yet still be THE expert or otherwise highly regarded in their area of expertise. Your post basically mocks a person for writing skills which could keep other potential posters from chiming in.
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post #773 of 2920 Old 06-19-2014, 11:41 PM
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Originally Posted by urapnes1 View Post
Your post could be taken as an insult to many highly intelligent people who simply do not have a mastery of the English language. Following MLA citation (or whatever format is accepted now), using proper punctuation, not bastardizing the English language, or using flowery language are a all nice and generally appreciated, but it is not required to convey a message. Someone could lack the communication skills yet still be THE expert or otherwise highly regarded in their area of expertise. Your post basically mocks a person for writing skills which could keep other potential posters from chiming in.
You aren't the first one to whine about how others post on this forum. Others have tried but made no impact. It's just the way internet forums are. Got any tips on jitter audibility or on how to separate sales pitch and helpful data?
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post #774 of 2920 Old 06-19-2014, 11:59 PM
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Originally Posted by spkr View Post
You aren't the first one to whine about how others post on this forum. Others have tried but made no impact. It's just the way internet forums are. Got any tips on jitter audibility or on how to separate sales pitch and helpful data?
I don't think what I wrote was whining, but rather a fair feeling that someone could take away after reading posts like that. You would never find that kind of repeated derogatory tone in a true professional setting without HR stepping in. I've seen people fired for similar actions. Personally, I'd just start permanently banning people

Not all forums are this way. CNCZONE is pretty well behaved.

As far as how to cut the crap and get back on topic...There is still a chance. I signed on to this thread to try to learn more about jitter. In the past I could swear I heard differences between CD players. I could describe what I was hearing, but never knew what jitter was. Always wanted to know.

As far as how to get helpful data, sure, but there has to be mutual respect amongst the contributors first. Unfortunately there is zero chance of that here.
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post #775 of 2920 Old 06-20-2014, 01:23 AM
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Somebody should flow-chart this thread.

I'll be back later...


equitech 1.5RQ > digits > miniDSP > behringer > benchmark > krell pre and monoblocks > reQuest
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post #776 of 2920 Old 06-20-2014, 01:49 AM
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I created this thread and so far we have managed to keep the noise down and technical level high.
Our perception of noise must be very different.
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post #777 of 2920 Old 06-20-2014, 03:52 AM
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Originally Posted by TVOD View Post
What is the clock on pins 10 & 12 used for?
Not audio.

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Originally Posted by TVOD View Post
A bit of semantics, using a stable clock as a reference is the same thing. If one XORs the stable clock and the jittered clock 90 degrees apart with a filter and did a FFT, shouldn't that show the jitter spectrally?
The XORing seems like extra work and for what because a stable FFT clock remains an essential ingredient in the measurement.

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I understand some of the the underlying debate is the audibility of jitter, but there was much discussion regarding HDMI. I see HDMI audio is somewhat similar to SDI embedded audio in that it's in the inactive video portion. Embedded audio is a mixed blessing, but I'll take it over dealing with 8 discrete AES stereo pairs. I really should pay more attention to these formats
I agree with your general point. This is really an Amir against the world argument. Like many novices he's read some badly written articles and made some naive measurements and come up with what he was programmed to believe are terrible numbers. But they are just numbers without their perceptual meaning.

He's been obfuscating requests that he do some good listening tests for months if not over a year. This is as close as he's gotten to such things. Unfortunately there are a fair number of people like him in the world.

Reality is that jitter is FM distortion is jitter is FM distortion. We've had audio gear with jitter for decades, only it used to be analog tape recorders and the like. Jitter is even possible with radio transmission due to variations in atmospheric conditions and reflections off of moving objects including tree leaves.

From a perceptual standpoint jitter has two dimensions - modulation frequency and magnitude. There is ample scientific literature stated in those terms, but for some reason people have been blinded to such obvious things. Notice that jitter has been traditionally specified in picoseconds, but that is by definition incomplete because it says nothing about the modulation frequency. The test files I've been circulating start out with huge amounts of jitter and go down in steps of about 2, from 2 milliseconds to 3 microseconds.

This is a high stakes game because some people have advanced their careers by blowing up the importance of fantastically small amounts of jitter.

Last edited by arnyk; 06-20-2014 at 03:55 AM.
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post #778 of 2920 Old 06-20-2014, 04:06 AM
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The highlighted area is common to all which no doubt is coming from my laptop source device. Different source devices will likely show different correlated noise.
Note that the alleged problem area is about 100 dB down. Yet another inaudible molehill being fluffed up into a mountain.

The threshold of hearing at the indicated jitter frequency of 7 KHz

can be found here:



The threshold of hearing is about the same as size of the 7 KHz artifact presuming a listening level of 105 dB. There would be additional masking from the music or drama being played but the artifact is so trivial we don't even have to go there.
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post #779 of 2920 Old 06-20-2014, 04:21 AM
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Originally Posted by arnyk View Post
I just added the next smallest jitter file: 30 Hz threshold jitter 0.00312.fla

to the archive at https://www.dropbox.com/sh/b35feharw...9KwuBTPbBa1JZa

Enjoy!
Ouch, sine still at the beginning


Training with A B already made it clear to me I couldn't hear the difference with this file I was hearing in the other files.


Test results with only a couple of trails.


foo_abx 1.3.4 report
foobar2000 v1.3.2
2014/06/20 12:49:13
File A: \\diskstationone\music\jitter\test\30 Hz threshold jitter 0.00312.flac
File B: \\diskstationone\music\jitter\test\no jitter.flac
12:49:13 : Test started.
12:51:57 : 00/01 100.0%
12:52:30 : 00/02 100.0%
12:53:44 : 01/03 87.5%
12:57:05 : 02/04 68.8%
12:58:15 : 03/05 50.0%
12:59:11 : 03/06 65.6%
13:00:14 : 03/07 77.3%
13:00:17 : Test finished.
----------
Total: 3/7 (77.3%)
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post #780 of 2920 Old 06-20-2014, 04:34 AM
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Originally Posted by amirm View Post
Hi Arny. Putting aside the fact that the last bit reads just like a subjectivist saying "trust your ears," why is it that when I asked you if you have ever documented any such listening tests, the only one was this amplifier test:



Arriving at this conclusion:



When we discussed this earlier in this thread, it seemed that were trying our damndest to disown its results. Why would we do more work like this only to have it be dismissed?

But sure, please create more of these tests, run them and report to us how well you could hear these distortions.
The bar has been set artificially high. Many of the listening tests that I've participated in are documented here:

http://home.provide.net/~djcarlst/abx_data.htm

Many of the techincal tests that I've done were documented at www.pcabx.com which is still acessible via the well-known wayback machine.

It's not the JAES, but its real.

Why would I do more work like this only to have it be dismissed as has been done with my previous work?

Quote:
Originally Posted by amirm View Post
It is good that you think that Arny. The problem is, you have to demonstrate it. Sitting right here, you have no measurements of broad set of AVRs to know what they do or don't, right? How can we be so clairvoyant as to know a priori what distortion a product has? I know I am not one tenth as smart as what is required to figure that out .

Seems to me, we should put the data forward and let the chips fall where they may. You yourself said we should run listening tests above only to say in a couple of paragraph later that none is needed because we have already made up our mind even though we lack the data.

If we foreclose the conversation as you are doing, then it will look like we are hiding something. We should not be partisan as to outcome of such tests. That is the fastest way in becoming the other camp .
Actually the web has a goodly number of AVR technical tests on the Sound and Vision web site, as well as Audioholics. Why do I need to reinvent the wheel?
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