On the subject of "ringing"

[Spacehound]

First it was 'jitter'. Now it's 'pre ringing'.

 

What's on next? 

[Spacehound]

28 minutes ago, sdolezalek said:

.....Is audio that special breed of science where data is irrelevant and "I heard a difference" is the gold standard???

Only for a crazy minority.

 

"The fuel gauge on my car says the tank is empty. Never mind, it's only data"

 

[Spacehound]

9 minutes ago, Spacehound said:

I wish I didn't keep hitting quote instead of edit. Never mind, the words are only data.

 

[Spacehound]

2 minutes ago, sdolezalek said:

 

I'm more worried about those who drive like their fuel gauge says full, when there's really nothing in the tank... 

Once when I bought a brand new (Ford) car it read full. "How kind, the dealer has filled the tank"

 

It stopped four miles down the road  

[Spacehound]

17 minutes ago, sandyk said:

 

 

 It is when backed up by correctly performed, positive DBT results, which many E.E.s claim ARE the " Gold Standard", until the results don't go the way they expected them to !

There is no such thing as a 'positive' blind test and no 'correct' or 'expected' answer.

 

All the tests are is 'can you tell ANY difference'? It's not 'Can you tell THE difference'.

Thus it is 'binary'  (yes or no) so  100% objective as unless you CAN hear a difference you CAN'T have a 'preference'

[Spacehound]

15 minutes ago, sandyk said:

 

 What a load of crap ! That may be the way they are SUPPOSED to work, but in the case of people like yourself, mansr etc.. it is almost always a case of prove what you are saying with DBTs ,(sometimes followed by " or STFU" ) just as with any other claim in every field where people report results that can't be reasonably explained.

Bollox.

I can't speak for mansr but I have never 'created' nor taken part in ANY kind of audio test, blind or otherwise, and I don't intend to.

Why?  I couldn't be bothered. Like most  others  I just buy (or sometimes make)  whatever takes my fancy.

 

"can't be reasonably explained"

Which sort of UNreasonable explanations do you prefer?

[Spacehound]

7 hours ago, John_Atkinson said:

 

As its frequency is at Nyquist, which is above almost everyone's HF cutoff frequency, you would think not. But when I discussed this with Karlheinz Brandenburg at an AES convention several years ago, he said that basically even if you can't hear the "ringing" as a tone, your brain could well be aware that something has happened when it starts and marks it as an acoustic "event." Then, when the peak is subsequently reached, that is marked as a spurious second "event," leading to confusion.

 

On the subject of the time-symmetrical ringing of linear-phase digital filters, I assume Robert Watts would disagree; see my comment on his "million-tap" filter at https://www.stereophile.com/content/chords-million-tap-digital-filter

 

Incidentally, I have recently been examining the time-behavior of A/D converter antialiasing filters and have found just one which captures a band-limited impulse without any ringing before or after: the Listen filter on Ayre's QA-9 converter, designed by Charley Hansen and Ariel Brown.

 

John Atkinson

Editor, Stereophile

If pre-ringing  actually exists in 'reality' then the filter must be made out of the electrical equivalent of thiotimoline.

Failing that it is merely an artefact of the measurement methods.

 

There is only one guy on this entire forum that might be able to convince me otherwise.

[Spacehound]

40 minutes ago, buonassi said:

 

Does preringing only affect HFs near Nyquist? 

It doesn't happen at all if Nyquist/Shannon is obeyed.

 

'Bob' Stuart and his shills  deliberately  use meaningless measurement methods so it looks 'broken' and then try to sell us a magical fix.

It's why Meridian stuff often receives  poor  'sound quality'  reviews, and that's even before he dreamed up  MQA. 

[Spacehound]

28 minutes ago, buonassi said:

 

 

are you sure you're not confusing aliasing/imaging with "ringing"?  Not trying to shut down the discussion, or insult you by any means.  It's me that has a lot to learn yet, especially about Nyquist and the "folding" that's involved with MQA.

I don't think I am but I wouldn't stake my life on it. It's only  audio.

 

Pre-ringing  breaks cause and effect so it can only be an artefact,  or what you see if you use an invalid measurement method. Which I suspect they are doing deliberately. (Even John Atkinson,  said  the measurement was "illegal" but later backed off via  obfuscation in the hope we wouldn't notice. The magazines' contempt for their readers is endless and it's not just Stereophile.)

[Spacehound]

1 hour ago, buonassi said:

It achieves absilThe effects of preringing can be done away with just by using a higher sampling rate with a super slow rolloff filter applied after 20khz.  So a benefit of MQA as I see it would be a smaller file size.  But do we really need that with today's storage and transmission technology?

 

Man do I wish SACD or even 96khz/16 bit PCM would've become the standard and ousted redbook.  We wouldn't be having this debate today.

 

edit:  The effects of ringing both pre and post can be done away with.

It varies by content but on average  an MQA file is no smaller than a regular FLAC file of the same 'nominal' resolution.

Though in practice, due to the need to make space for  the 'folding',  the resolution of a MQA file is less, 17 bits at the most rather than 24.  Nothing is free in the real world.

 

And as MQA data above 96K is totally fake, even including the noise,   with an MQA-claimed  192 file  they are using the doubled size for nothing that is 'true'. This won't matter audibly, but what's the point other than making your DAC say 192?

 

The  more you look the more you find MQA is a total scam from beginning to end. It achieves absolutely nothing and may often audibly degrade the sound. 

[Spacehound]

16 hours ago, Ralf11 said:

 

when coupled with a lack of methodology it is no surprise that people reject this

 

if you want to be believed you will need good strong evidence

 

unusual results require unusual proof -- and anything appearing to contravene known physical laws is indeed unusual

His methodology is superb:

 

"Martin Colloms was able to....."  (one occurrence, used many times)

or

"Many members agree"  ("many" appears to approximate 5, used many times, it is not known if it is the same 5 every time but you won't get on his 'approved testers'  list if you fail the initiation ceremony)

or

Insults

 

Beat that.

[Spacehound]

21 minutes ago, John_Atkinson said:

 

Look more closely at the graph using the color coding for the traces I supplied in my earlier posting.

 

John Atkinson

Editor, Stereophile

Can we  assume that after Jim's  "illegal"  impulse this is the 'approved' one?

 

My impulse is to think yours is  obfuscation.

[Spacehound]

15 hours ago, mansr said:

New physics is pretty much confined to high-energy accelerators these days.

Shame there's not a downtick.

One day there might be.

[Spacehound]

2 hours ago, Shadders said:

Hi,

I am surprised that pre/post ringing has not been resolved or defined as an issue in the audio world.

 

How can such an issue be continually discussed as either it exists, or does not exist, and where and how it occurs ?.

 

If the AES was a professional organisation, then surely this aspect would have been well understood by the participants/members ? and published papers on the effect presented for the edification of all ?

 

Regards,

Shadders.

The AES isn't a professional organisation in the  generally accepted sense.

[Spacehound]

2 hours ago, mansr said:

First of all, pre-ringing isn't a well-defined term. In fact, it is never used outside of audio. Let us thus define it for the sake of this discussion as an impulse response having at least one negative excursion prior to the (positive) peak.

 

Symmetrical impulse response plots are often centred around time zero. On the face of it, this amounts to (part of) the response preceding the input. Such a system is termed non-causal and cannot be physically realised. We nevertheless use this representation because it is mathematically convenient. Now remember, we are dealing with a time-invariant system, which means a time-shift of the input results in a time-shift of the output. Thus, provided the impulse response is finite, we can make it causal simply by shifting it such that it becomes zero for all negative time values. The only effect of this is the addition of a constant delay to the output. Importantly, the frequency response is not affected.

 

In practice, a digital filter incorporating such a time-delay is trivially constructed. An all-analogue realisation is trickier, although it can be accomplished through the use of various delay elements.

 

Have I convinced you yet?

Yes you have,, it is causal but doesn't appear so how it's usually measured and calling it 'pre' is silly.

 

But you presume too much. I was expecting the answer to come from s....k 

[Spacehound]

4 hours ago, buonassi said:

just got caught up.  in reading the last couple pages, I keep seeing attempts to prove ringing doesn't exist or shouldn't matter if it does.  I'm not even going to try and pretend I can follow some of the posts as I'm not a physicist or electrical engineer.   

 

if ringing doesn't exist, or doesn't matter, then why are there different filter designs and why do they sound different to me?  Are the opponents of ringing going to assert that I'm imagining the differences?  That "expectation bias" is to blame?  

 

I'm not going to state that one filter is better than another.  But am I the only one who can admit to hearing a difference among them?  Have all the hours I've scrutinized iZotope upsampling parameters, observing the rolloff steepness in an RTA, and noted sonic differences all been a hard lesson in realizing I'm "drinking the coolaid"?

My DAC has several different  filters and also supports MQA. Though  thankfully it automatically switches all the MQA stuff off  completely when it is not playing an MQA file and reverts to the filter you had previously selected.

 

Which  filter is "best"? Dunno, I don't have a clue how it is supposed to sound.

 

And neither do you   

[Spacehound]

15 hours ago, Jud said:

 

No test requiring a verbal answer as to conscious, subjective perception should be referred to as  "100% objective."

 

But rather than jumping down this particular rabbit hole yet again, I'll be interested to read through the rest of the thread and learn something from folks who are far more informed than I am on the topic of digital audio filter behavior.

Sure it is.

We are doing a 'survey'  even if it's only of one person, and asking the listener whether  he can hear a difference or not.  That's binary.

What happens between his ears and his mouth is irrelevant.

 

Also what he says doesn't have to be true, true/false is binary too,  Nor does any overall result if there are lots of people. 

(I'm not having you  as a lawyer, you don't even know that things can be both objective and wrong )

[Spacehound]

11 minutes ago, audiventory said:

 

In context of ringing research, I'd ask hearing test participant "What is better?" (linear or "quasi-analog" [minimal phase filter]).

That instantly changes what should have been an objective test  into a possibly  incomplete  list of individual, unrelated,  personal preferences, even if  there is no difference at all - you have prompted them  into thinking there is one.

 

So it  is totally worthless.

[Spacehound]

19 minutes ago, audiventory said:

 

Big numbers (tens thousands) and clustering (tested samples, partisipant skills, etc.) allow to reduce uncontrolled individual biases.

 

I don't know what is practical benefits of researching "different or not". As example, linear and minimal phase filters sounds differently. What we can to do for sound improvement in a future audio units after the researching?

 

Sure they can. But it has nothing whatsoever to do with my comments.

 

In practice? If you cant  hear any difference buy the lower cost box.

That's why most  Hifi manufacturers HATE blind tests and will come up with near endless utter nonsense to (fail to) convince sane people they don't work. It is why most US manufacturers (particulary)  have totally abandoned  the  realms of high fidelity and gone for 'impressive' instead.

[Spacehound]

31 minutes ago, audiventory said:

 

As developer/manufacturer, I use available researching results (including blind and ABX tests) to improvement of subjective perceived sounding.

Me need to know what is sound better. Of course, knowledge that there is no difference is useful. But also need to know, that to do for sound perception improvement. It allow to move to target easier way.

 

Blind tests are too complex. It is very hard work, that demands serious knowledges about subject and measurements, performing accuracy, correct using of equipment and fixing subtlest details https://samplerateconverter.com/educational/hifi-blind-test

Also need to separate 2 direction of perceived sound improvement:

• high fidelity (low distortion level);
• sound enhancers (tube, vynil, tape, analog circuits, spatial improvements, it emulators).

I think, next jump in quality, expected us in spatial reproduction (sound hologram) https://samplerateconverter.com/content/where-limit-audio-quality

Nothing after the source can improve on it. They  either degrade it, leave it alone,  or alter it  to suit your personal preferences, which means it has left  the 'high fidelity' arena, which is what many of us pay for  So 'enhancers' don't exist.  I exempt room treatments from this though I don't use them.

 

Blind  tests can reveal price/performsnce ratios. Nothing else.

 

What do I do?

I will look at speaker reviews to see if they have  a flat frequency response/good phase performance. If not, I won't buy them.

Everything else I just buy what I take a 'fancy' to and can afford.  I almost never  listen before buying it and have not done so for at least ten years. It's the same with cars - it took me all of  15 minutes to make up mind, go to the Mercedes dealer, and buy one,  mostly because he's the nearest car dealer to where we live (UK).

[Spacehound]

23 minutes ago, audiventory said:

 

What is source? Acoustic wave before microphone?

 

 

I'd looks wider to the matter. You forgot about development. It is almost impossibly to made home blind test.

 

 

Technically correct measurements have more than pair dimensions. Flat frequrency response say nothing about non-linear distortions.

 

There is need to scan linearity of in/out voltage for full frequency band including ultrasound area. And when you have these results, there is very complex analyzis stage with accounting of psychoacoustics.

 

 

 

I more sensitive to car, that I ride But I can understand this approach in other things.

No. It's the CD, file or whatever. They are not playing live in our rooms so that is all  most people have

 

Yes,  you cannot  easily  do good blind tests at home. 

 

I agree with the rest.

 

My car is an SLK 55, small but with a  5.5 litre V8.  It  does what I expected it to do and a lot more   

 

 

[Spacehound]

16 minutes ago, Jud said:

 

Ah, the things you don't know about blind testing.

 

There's a lot in the scientific literature. If you're curious about the various complexities, you can start out looking at one of them by doing a search for the Iowa Gambling Task, and thinking about the implications for tests requiring conscious verbal responses. 

.