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Old 23rd December 2012, 02:42 PM   #31631
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Quote:
Originally Posted by Jakob2 View Post
Could it be that you are slightly biased?

I haven´t read any publication so far related to audio compression, but these guys are normally quite serious, see for example:

"Toward a Direct Measure of Video Quality Perception Using EEG"

IEEE TRANSACTIONS ON IMAGE PROCESSING, VOL. 21, NO. 5, MAY 2012

http://iphome.hhi.de/wiegand/assets/...o-qual-EEG.pdf

Btw, Oohashi et al. published about the "hypersonic effect" which means signal content above 20kHz not ">100kHz" .
That was a typo, sorry. What, me biased? Interesting stuff, lots of unanswered questions not the least of which is that only a subset of the population has strong enough EEG's at this time. Are they somehow different?

I like his paper on using thier computer brain interface to play pinball.
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Old 23rd December 2012, 02:43 PM   #31632
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The EEG thing has interesting implications.

Reminds me of that test where researchers found that people could not hear sound above 20kHz, or at least they said so, but there was EEG activity (so they said).

My question would be: if there is EEG activity but no consious knowledge, does that represent 'hearing' it?
In other words, even if people said they didn't hear a difference, would they still vote as if they heard a difference, in a controlled test?


jan
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Old 23rd December 2012, 02:49 PM   #31633
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Quote:
Originally Posted by jan.didden View Post
The EEG thing has interesting implications.

Reminds me of that test where researchers found that people could not hear sound above 20kHz, or at least they said so, but there was EEG activity (so they said).

My question would be: if there is EEG activity but no consious knowledge, does that represent 'hearing' it?
In other words, even if people said they didn't hear a difference, would they still vote as if they heard a difference, in a controlled test?


jan
Let's get Fremer and Randi wired up.
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Old 23rd December 2012, 02:57 PM   #31634
Jakob2 is offline Jakob2  Germany
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Quote:
Originally Posted by jan.didden View Post
The EEG thing has interesting implications.

Reminds me of that test where researchers found that people could not hear sound above 20kHz, or at least they said so, but there was EEG activity (so they said).

My question would be: if there is EEG activity but no consious knowledge, does that represent 'hearing' it?
In other words, even if people said they didn't hear a difference, would they still vote as if they heard a difference, in a controlled test?


jan
In the mentioned publications by Oohashi et al., they tried to find out and noticed that the listeners could not detect the high frequency content (>20 khz) if that part of the spectrum was presented alone, but that their eeg and pet scans differ to a significant degree and that they rated the perceived audio quality higher as well, if the full signal content (which means audio band + content >20Khz) was presented.
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Old 23rd December 2012, 03:05 PM   #31635
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Jokob, I didn't read that paper, and you don't need to do my legwork for me, but do you know if those tests were reasably controlled?

jan
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Old 23rd December 2012, 03:08 PM   #31636
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As in any technical paper written you have to be able to discern the facts from the sometimes glaring errors or omissions. I think it was Gerhard that sent me a link on a certain thread that had to do with the magnetic motor design of a loudspeaker. In this article which is well written there are obvious facts that were disregarded in the asymmetry of the the stray magnetic filed surrounding the gap and the use of overhung voice-coils in this arrangement. So do I disregard the entire premise of the article because of this? No. The basic science was correct but I had to make a judgement call that the conclusions were not completely correct. I still learned something but knew empirically that there was a flaw in the argument. I think that this goes for many technical discussions. You can still take away information from the discussion, it does not mean that you have to take all of the information as gospel. As we see from reading the post from some of the smartest people here probably in this field people still can make a mistake or overlook something. Does that mean you should stop reading the thread because someone made a mistake or overlooked a particular flaw that you may have noticed. That in itself would be flawed or biased thinking on its own. Do we disregard Einstein just because somewhere he made an incorrect judgement or did not have some new modern method or proof and throw out all his work and call him a mistaken physicist and demand a proof? Take what you can from the discussion here and stop attacking because of your own preconceptions. If that is the case you are adding nothing to the discussion. Point out an error you see or question, that is the much smarter in My Opinion as to how you can add to the discussion. I know that at times not here but in other threads that I read on loudspeakers I do not correct some misconception as I have some knowledge I want to withhold. If John or Scott or Richard gave every thought away that they knew they would give away many years of practicing this craft and some insightful moment that they had at some point that they can use to their personal advantage in business. That would just be stupid on their part if they are involved in any commercial endeavor. If you are retired and just want to share your knowledge then perhaps you can give away those thoughts. But in this forum it is clear that John is still in this business to make money to live on. Do you expect him to give away everything to us here? Then all of those years of practicing this art will take away all of his personal advantage and worth to others who do need him to direct them in the correct direction to create a profitable product. This is a forum, not a doctoral thesis that we are looking for a flaw in. Take what information you find reasonable and helpful as a gift and question honestly any errors you may find. Perhaps you will be right and John will learn something, perhaps you are wrong and you will learn something. Can't we all just get along.
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Old 23rd December 2012, 03:23 PM   #31637
Waly is offline Waly  United Kingdom
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Originally Posted by Kindhornman View Post
Perhaps you will be right and John will learn something.
Unlikely.

Show me an instance where someone won a technical argument with JC. Everything else is either inferior (or "mid-fi"), or it was done 40 years ago.
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Old 23rd December 2012, 03:25 PM   #31638
Jakob2 is offline Jakob2  Germany
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Originally Posted by jan.didden View Post
Jokob, I didn't read that paper, and you don't need to do my legwork for me, but do you know if those tests were reasably controlled?

jan
The paper is well worth a reading:

Inaudible High-Frequency Sounds Affect Brain Activity: Hypersonic Effect
(Pdf download of the article is free)

It was a double blind test and the participants answered a complete scoreboard for the various parameters of the subjective perceived audio quality.
The authors even used Sheffe´s Method for multiple comparisons during the statistical analysis which is quite restrictive in favor of avoiding alpha errors.

I´d say they did a good research job but it was still not perfect.
The team published some more papers in which they tried to gain further insight and find explanations for some open questions.

Other researchers followed with some more papers on the audibility (most were published in the JAES) of high frequency content, but afair no one used the combination of EEG/PET scans with sujective listening tests.

The results were not really consistent......

Last edited by Jakob2; 23rd December 2012 at 03:30 PM.
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Old 23rd December 2012, 03:30 PM   #31639
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I pop in here, now and then, because I value John's and others' knowledge and experience, very much, and often pick up interesting or useful or entertaining or enlightening information.

I was taught, but also believe it is obvious, that "one should not look a gift horse in the mouth". That means that if you receive something for free, it would be rude to examine it for faults or flaws, much less complain about them out loud.

In the case of receiving a gift of information, such as technical insights or techniques or other knowledge, where archived public exposure exists and discussion ensues, it could be productive and acceptable to ask and answer questions in attempts to increase the benefit gained from the information, for both current and future readers and participants, and which might even benefit the gift-giver (and the world at large) by creating a better archive of their knowledge (since we can assume that by giving such a gift, the giver wants to have their special knowledge preserved and be able to benefit others).

But it is important to note that participation is voluntary. It is also important to note that interpreting and/or using the information is voluntary, and that every individual, both now and in the future, is responsible for the correctness of their own interpretation or use of any information. ("This ain't no *******' peer-reviewed IEEE journal.")

So, while certain types of people might feel the urge to "protect" others from what they perceive as "wrong" information, there is a point where that would become rude, in this context. (I would love to make some political analogies, here, if it were allowed in this forum.)

Last edited by gootee; 23rd December 2012 at 03:34 PM.
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Old 23rd December 2012, 03:39 PM   #31640
gootee is offline gootee  United States
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Quote:
Originally Posted by Kindhornman
Perhaps you will be right and John will learn something.
Quote:
Originally Posted by Waly View Post
Unlikely.

Show me an instance where someone won a technical argument with JC. Everything else is either inferior (or "mid-fi"), or it was done 40 years ago.
It seems obvious to me that John is the type of person who loves learning. And if no one here has ever won a technical argument with him, then wow, I will start looking at everything he says as "gospel"!
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