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Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #700
@amir
So what? We neither argue about codecs nor older rate converters.
Is troll-adiposity coming from feederism?
With 24bit music you can listen to silence much louder!

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #701
btw. i once saw nice pictures done with iZotope RX that shows the ringing together with its spectral distribution.
That image was used in this thread from 2008.


Thanks, this must have been it. Now we need this for a 21kHz filter to show where this ringing happens. Hopefully this will help to understand.
Is troll-adiposity coming from feederism?
With 24bit music you can listen to silence much louder!

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #702
Amir can't defend the frivolous BS paper, thus has been reduced to one dive down the rabbit hole after another and quoting papers from a guy who says this:

Let's start:  "how do you even imagine that one can hear a difference between two systems, one with noise 98 dB down and the other 146dB down, when the level is set to peak at 96dB?"

How do you explain how "obviously difference" fails to show up in even the worst kind of ABX test?

I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

Bear in mind the hard evidence for the persistance of loudness memory while you're at it.

I have my doubts that SACD or DVDA are much, if any, of an improvement, but the test is just blisteringly hard to run, and more likely to respond to artifacts, either positively or negatively, than it is to actual differences. Time alignment, level alignment, frequency response in-band can all throw it positive, lack of training, bad test environment, bad time alignment, etc, can also cause false negatives. Subject verification, likewise, is an important issue.

So, I remain undecided, but I note that I own a lot of CD's and not a single SACD or DVDA, except for some people have sent me.

And
Quote
In the usual stereo audio presentation, a partial sound stage consisting primarily of the front elements of the sound stage is created by two channels, either sampled from several microphones set in the original sound field or more often by a mixdown of many microphones placed both in proximity to the performers and out in the hall to capture the ambience. The information presented by the two channels, in either case, is a small fraction of the information in the original sound field. Additionally, this fraction is presented to the front of the listener. The presentation does not create an envelopment experience, where one is immersed in the original sound field, as the information is not present.


I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

Amir is implying JJ doesn't understand his own presentations. He's got it reversed, as usual. 

cheers,

AJ
Loudspeaker manufacturer

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #703
@amir
So what? We neither argue about codecs nor older rate converters.

??? Neither is the topic of JJ's presentation.  Once more those are side remarks.  The paper is about anti-aliasing filters.  I will explain more but it is strange that I can't get this simple message across.
Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #704
Quote

In comparison testing I have done, switching amplifiers using the classic class D configuration always sport incredible low frequency control and power. They beat out linear class AB amplifiers almost regardless of price. What they give up though is high frequency fidelity which I find somewhat harsh. The distortion is highly non-linear and challenging to spot but it is there. The Mark Levinson No 53 is the first switching amplifier I have heard which does not have this compromise. Its bass is amazingly authoritative: tight and powerful. Yet the rest of the response is absolutely neutral and pleasant.

If you have not heard these unique amplifiers, I highly encourage you to come into our showroom for a listen. We have a pair on hand driving our Revel speakers. I am confident that they will improve the sound of your current speakers given the ease with which they can drive any load regardless of how difficult they might be (and many high-end speakers are difficult to drive). We are happy to let you evaluate them with your own system to see the benefits of this technology. Hearing this amplifier was an eye-opener for me. I think it will be for you too.


 


Can anybody explain to me how to distinguish the above 2 paragraphs from the usual subjectivist false claims that we all know and find to be unfounded, senseless and reprehensible?

This is not a topic about amplifiers.  I am unclear why there is no moderation to stop this off-topic branch.

But since there is so much interest about it, I created one on audibility of amplifier distortions: http://www.hydrogenaud.io/forums/index.php?showtopic=107604

Please take your amplifier arguments there.
Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #705
On a sidenote i remember how benchmark media in an official forum post declared ringing in their hardware as non-issue.
Meridian has a patended solution against it with their apodizing filter so interest in it to be an issue.
Is troll-adiposity coming from feederism?
With 24bit music you can listen to silence much louder!

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #706
As I just correct Arny, JJ's slide very clearly confirms the same that the brain is not a DSP machine where it captures a bunch of samples and then decides what it means.


Never said it does. Amir you can argue with yourself as much as you wish, at least as long as the moderators pass on the Off-topic nonsense.


Just to review, Amir claimed:  "We hear each one of those samples as they come."

On his first attempt to spin out this hole, he try to change what he said.  He also tried to change what JJ said.

On his second attempt to spin his way out of this hole, he's trying to change what I said.

So here is the question - who else is he going to misquote? ;-)


Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #707
Amir can't defend the frivolous BS paper, thus has been reduced to one dive down the rabbit hole after another and quoting papers from a guy who says this:

The paper doesn't need me to defend it.  It has won an award for the best peer reviewed paper at this  year's AES conference.  Having you dispute it is like a fly hitting the windshield of the car slowing it down.

Quote
I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

You quote his forum posts, I quote his presentation to Audio Engineering Society:

[/quote]
The above slide could not be more clear.  Don't confuse the JJ that is giving a formal presentation with one that is in forums smacking people like you around for fun  .  And of course your link is from a couple of years ago, prior to the publication of the listening test results we are discussing.


Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #708
Quote
I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

You quote his forum posts, I quote his presentation to Audio Engineering Society:


Where does it mention hi-res? It doesn't mention it anywhere in your own quote. It just says it may affect your choice of sampling frequency. That could be 20.000001Khz or 14KHz or 19KHz or 42,000,000MHz.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #709
Amir can't defend the frivolous BS paper, thus has been reduced to one dive down the rabbit hole after another and quoting papers from a guy who says this:

The paper doesn't need me to defend it.  It has won an award for the best peer reviewed paper at this  year's AES conference.  Having you dispute it is like a fly hitting the windshield of the car slowing it down.

Quote
I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

You quote his forum posts, I quote his presentation to Audio Engineering Society:


The above slide could not be more clear.  Don't confuse the JJ that is giving a formal presentation with one that is in forums smacking people like you around for fun  .  And of course your link is from a couple of years ago, prior to the publication of the listening test results we are discussing.
[/quote]


What's clear is that correcting severe and obvious errors and misrepresentations in certain people's posts doesn't change their behavior. The above quote is out of context, and its meaning is further clarified by other slides in JJ's presentation.

Please see this post made to this thread in the past day for a clarification of the misrepresentations made above:

http://www.hydrogenaud.io/forums/index.php...st&p=882429

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #710
Let me highlight a part of JJ's slide that Amir curiously neglects .

A SPL range of 6dB -120dB being 'more than sufficient' for presentation, suggests that JJ is considering corner cases (i.e., rare cases) where 'presentation' on CD would not suffice. 

This is pretty much the sort of case the whole  hi rez-for-the-home edifice is built on.  The vast majority of recordings ever made and offered for home listening would not require such a range.  Certainly no *analog tape* recordings!  And emphatically never any presentation in vinyl format, despite the beloved status of vinyl amongst 'golden ears'.

It accords with JJ also saying  "I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener."

It would be rare indeed to find a case where the extra DR and bandwidth that high rez offers 'mattered'  to a listener at home the way, say, different mastering EQ and compression 'matter', room correction 'matters', or more delivery channels 'matter'.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #711
And of course your link is from a couple of years ago, prior to the publication of the listening test results we are discussing.

Liar. Part of that quote is from Aug 2014 and I have linked it directly multiple times in this thread, so there is no ambiguity and to stave off typical Amirspin.
There is absolutely nothing in this doctored BS paper that would conflict with anything I've read JJ state over multiple fora/presentations. There is probably very good reason why he wanted to offer PSR at 320kbps. Knowing fully well it would blow away your sides 2ch 24bit $cam.
Oh, he used Hafler AB amps too, for all the bass needed, not blingy 50k Class D $cam-amps.

His silence here is to save his old boss from further humiliation.
Or maybe he enjoys it. Who knows? 

cheers,

AJ
Loudspeaker manufacturer

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #712
Let me highlight a part of JJ's slide that Amir curiously neglects .

A SPL range of 6dB -120dB being 'more than sufficient' for presentation, suggests that JJ is considering corner cases (i.e., rare cases) where 'presentation' on CD would not suffice.

Sorry no.  His data is not based what is rare and what is not.  But rather, through a number of slides demonstrating the required dynamic range that would capture what we can hear.  This is the slide on the top side:



The hearing system uses a electromechanical gain stage to slide the limited dynamic range up and down through stiffening of OHC.  See my post on AVS which may be easier to understand than JJ's: http://www.avsforum.com/forum/91-audio-the...ml#post24254752

The lower limit is described such by JJ:



Now you see the 6 db reference.  Again, my link above has a simpler explanation involving the brownian motion that sets the lower limit.  JJ makes a good point about mapping this to ERB and hence getting 6 db unlike 0 db I assumed there.  That gets you 114 db or 19 bits.

Any format that cannot present this dynamic range is missing what the hearing system can capture in a live situation.

Speaking of that topic which is not covered by JJ, you can read Fielder's JAES presentation on research he did by measuring the peak dynamic range of concert halls and their noise floor (accounting for conversion of noise to ERB as JJ suggests).  He arrives at a requirement of 120 db there just the same.  See my version of that write-up in the article I wrote for WSR Magazine: http://www.madronadigital.com/Library/RoomDynamicRange.html

CD as JJ clearly mentioned is a compromise here.  Since we can adopt higher dynamic range formats with zero playback equipment cost to us, or any break in compatibility, there is little justification to stick to that spec when the physical format itself is becoming irrelevant over time.
Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #713
Quote
I have yet to see a whit of evidence that "high-rez" matters for final presentation to a listener.

You quote his forum posts, I quote his presentation to Audio Engineering Society:


Where does it mention hi-res?

Who is buried in Elvis' grave?
Quote
It doesn't mention it anywhere in your own quote. It just says it may affect your choice of sampling frequency. That could be 20.000001Khz or 14KHz or 19KHz or 42,000,000MHz.

Which one of those is supported by your audio hardware?
Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #714
Which one of those is supported by your audio hardware?


What has that got to do with the quote you posted? Which again doesn't mention hi-res, just different sample rates.

You really are the master of avoiding answering questions. Are you a politician?

 

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #715
In 29 pages, has anyone mentioned the other Bob Stuart co-authored paper from the same AES conference session? Number 9178?
http://www.aes.org/e-lib/browse.cfm?elib=17501

It's not off topic. It includes very similar discussions. It includes very different ideas. It's classic Peter Craven territory. In one element, I thought "they're doing lossyWAV with the blocksize equal to one track!"

Cheers,
David.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #716
Speaking of that topic which is not covered by JJ, you can read Fielder's JAES presentation on research he did by measuring the peak dynamic range of concert halls and their noise floor (accounting for conversion of noise to ERB as JJ suggests).  He arrives at a requirement of 120 db there just the same.  See my version of that write-up in the article I wrote for WSR Magazine: http://www.madronadigital.com/Library/RoomDynamicRange.html


As I've mentioned before I've loaded my Kindle with every issue of the JAES since 2001 and am working my way through them. In one article I noticed a comment that while it seems like he never published it, Fileder has mentioned in public that he did some research that showed that the average person listens to A/V at 70 dB SPL.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #717
Which one of those is supported by your audio hardware?


What has that got to do with the quote you posted? Which again doesn't mention hi-res, just different sample rates.

You really are the master of avoiding answering questions. Are you a politician?

You were asking questions whose answer was in the very slide you were referencing.  So I told you that with the reference to Elvis.  The answer was given albeit in a light-hearted manner.

Since it is still not clear, I will go ahead and provide the detail.  The phrase "hi-res" is a generic term and one coined in forums.  Its absence in a presentation has no meaning for you to note.  You need to read the content of the presentation to get the answer you are seeking.

CD's spec is 16 bits.  JJ's presentation says you need 19 bits to cover the sensitivity range of the ear.  And what gives you that in the marketplace is 24 bits which is the next jump from 16.  That makes his requirement "hi-res" as in higher resolution than the CD.

Likewise, when someone says you probably need to worry about sampling rate to produce 20 Khz, they mean something better than 44.1.  The next incremental value that is standardized in the industry is 48 Khz.  And you go up from there to 88.2, 96, etc.  There is no such thing as 22.00001 Khz and other random values you threw out.

These are the requirements for transparency.  You are welcome to keep dialing them down as you prefer.  But please don't mess with my dials .

Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #718
JJ's presentation says you need 19 bits to cover the sensitivity range of the ear.


Two words: Flat PSD

The same presentation says:

"Given the noise in the modern world, 16 bits is probably sufficient in most places."


Say Amir, have you ever heard of perceptually shaped dither? If you have heard of it, do you have problems with its use?



Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #719
JJ's presentation says you need 19 bits to cover the sensitivity range of the ear.

Two words: Flat PSD
The same presentation says:
"Given the noise in the modern world, 16 bits is probably sufficient in most places."

Not my copy of the presentation.  That aside, not interested in "probably sufficient."  That means transparency is not achieved for all content and all people.  We have a format that does that and it is the source file prior to down conversion.

Quote
Say Amir, have you ever heard of perceptually shaped dither? If you have heard of it, do you have problems with its use?

Where I buy my music, they don't list what type of dither was used to produce the 16/44.1 from its higher resolution stereo master.

Remember, the best use of noise shaping is when your sampling rate is higher so that you can park the noise in the ultrasonic range where we know it is inaudible.  Trying to stuff it in the audible band below the threshold of hearing is a tougher matter as you have to make sure my hearing is not better than that curve.  Whereas I know I can't hear ultrasonics, noise or otherwise.

This is why I say if the CD had picked 48 Khz like the professional field had done, we would be far better off.
Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #720
JJ's presentation says you need 19 bits to cover the sensitivity range of the ear.

Two words: Flat PSD
The same presentation says:
"Given the noise in the modern world, 16 bits is probably sufficient in most places."

Not my copy of the presentation.  That aside, not interested in "probably sufficient."  That means transparency is not achieved for all content and all people.  We have a format that does that and it is the source file prior to down conversion.


The false claim here is the presumption that content with higher sample rate and/or word length exploits it. With 24/96 there is no content in the real world that exploits it. The musical selection used in the Meridian tests was a good example - the noise floor was only about 70 dB below peak levels and thus easily handled with 16 bits and best practices. Actually best practices would not be required, merely good practices such as avoiding RPDF dither should suffice.

Quote
Say Amir, have you ever heard of perceptually shaped dither? If you have heard of it, do you have problems with its use?

Where I buy my music, they don't list what type of dither was used to produce the 16/44.1 from its higher resolution stereo master.

JJ and I agree, as it was produced and as it will be most likely used, won't matter.

Quote

Remember, the best use of noise shaping is when your sampling rate is higher so that you can park the noise in the ultrasonic range where we know it is inaudible. 
[/quite]

Ignores fact that noise shaping generally puts the noise below the threshold of hearing, and in the case of any real  world recording the noise is also well below ambient noise.


Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #721
More blustering and misdirection from Amir.  Does he ever cease?

JJ notes that as we approach 120dB SPL, listening becomes *dangerous*. (I note Amir didn't highlight that part).  JJ also knows what the absolute lower SPL limit of detectability is limited to the sound of atoms impinging on our ears, audible under conditions of extreme quietitude.

Someone please point me  to recordings of real-world events, and playback in real-world rooms, where this matters.  We're talking corner cases again.
Do you really think all the audiophile ranting and raving about how bad CD sound is, has to do in reality with *any* of that?

re: attaining 'high fidelity' at home:

ELEPHANT IN THE ROOM: 
bad mastering + bad in-room response at the listening position + too few delivery channels to provide spatial realism

FLEA IN THE ROOM:
0Hz-22kHz band inadequate to pass signals > 22kHz  + 96dB dynamic range* inadequate for signals ranging 120dB


And which one do the Amirs of the world push as the problem that needs addressing? 

_________________

*more than that , with noise-shaped dither...up to 120dB 'effective' DR. As Monty notes:

Quote
Our -96dB noise floor figure is effectively wrong; we're using an inappropriate definition of dynamic range. (6*bits)dB gives us the RMS noise of the entire broadband signal, but each hair cell in the ear is sensitive to only a narrow fraction of the total bandwidth. As each hair cell hears only a fraction of the total noise floor energy, the noise floor at that hair cell will be much lower than the broadband figure of -96dB.

Thus, 16 bit audio can go considerably deeper than 96dB. With use of shaped dither, which moves quantization noise energy into frequencies where it's harder to hear, the effective dynamic range of 16 bit audio reaches 120dB in practice [13], more than fifteen times deeper than the 96dB claim.

120dB is greater than the difference between a mosquito somewhere in the same room and a jackhammer a foot away.... or the difference between a deserted 'soundproof' room and a sound loud enough to cause hearing damage in seconds.



Agrees with what J. Robert Stuart himself wrote:
Quote
It is possible to exploit the frequency-dependent human hearing threshold by shaping the quantisation
and dither so that the resulting noise floor [of 16-bit audio] is less audible.

Figure 19 shows how the Meridian 518 (an in-band shaper) can allow a 16-bit transmission channel to
have a subjective noise floor more equivalent to a 20-bit ‘simple’ channel.
If such a channel is to be
useful, the resolution of the links in the chain before and after the noise-shaped channel must be
adequate. In simple terms, this means mastering and playing back using well-designed converters
offering at least 20-bit resolution.



So, again, if you do Redbook 'right', you perceive 'hi rez' sound.  But let's not tell people that when CD playback 'bad' it's because something's been done wrong...let'$ tell them that CD $ound i$ bad because CD i$ bad.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #722
The false claim here is the presumption that content with higher sample rate and/or word length exploits it. With 24/96 there is no content in the real world that exploits it.

Anyone can declare anything.  You need to back such statements Arny.  Not just declare it.

Here is me backing the need for 120 db/20 bits to accomdate all cases: http://www.madronadigital.com/Library/RoomDynamicRange.html.  There are two journal of AES references at the end from two AES Fellows.  You have something like that which says what you just said?

Quote
The musical selection used in the Meridian tests was a good example - the noise floor was only about 70 dB below peak levels and thus easily handled with 16 bits and best practices.

Here is the measurements from Stuart's article:

At 3.5 Khz and eyeballing it, the noise floor of the content is around -25 db spl and the peak 90 db.  So the total range is 90+25=115.  How did you get the 70 number?

Amir
Retired Technology Insider
Founder, AudioScienceReview.com

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #723

At 3.5 Khz and eyeballing it, the noise floor of the content is around -25 db spl and the peak 90 db.  So the total range is 90+25=115.  How did you get the 70 number?


Nice job of cherry-picking from misleading data. The noise spectral density is said to have been measured using a 1 Hz bandwidth, but in fact the ear hears in critical bands which are about 1000 times wider around 3.5 KHz. The well  known fallacy of measuring the perceptual qualities of music or ambient noise in narrow, constant frequency bands is being exploited.

Thanks for pointing this misleading data out, its another serious problem with the article. If you are going to do comparisons like this the frequency bands have to be perceptually relevant.

If you check the scientific literature, you'll find that a lot of noise measurements are done in octave bands. Pros know this, amateurs generally don't and make the mistake shown above.

The cherry picking part is the fact that the signal level shown (in a mistaken way) varies over a 40 dB range right around 3.5 KHz, and you picked your number from among the higher numbers in this range.

Audibility of "typical" Digital Filters in a Hi-Fi Playback

Reply #724
Hi Amir,

In another thread here, you linked a page with this article on your sales store website, titled "Audibility of Small Distortions" By Amir Majidimehr, the self assessed objectivist/non-hobbyist.
Quote
The “Q” indicates how steep the resonance is in the frequency domain.  In the time domain (not shown), the higher the Q, the more “ringing” the system has.  Ringing means that a transient signal (think of a spike) will create ripples that go on for some time after they disappear.  An ideal system would reproduce that transient with zero ringing.  The higher the Q of a resonance, the more ringing the system has. Reading what I just wrote, if I asked which one of the resonances on the right is more audible, you will likely say High Q.  It seems natural that it has the highest amplitude change and more time domain impact per my explanation.  Yet listening tests show the opposite to be true!  The Low Q is more audible.



Here is the measurements from Stuart's article:


What do you make of this and what would the implications be for audibility with and without typical and atypical filters?
Is it possible for out of band resonances to create harmonics in band?

cheers,

AJ
Loudspeaker manufacturer

 
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