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What is the rationale behind the prohibition of DBT discussion? - Page 16

post #226 of 454
Quote:
Originally Posted by badmonkey View Post

 


So why don't you take the clearly more rational choice of "freeing" the forum in general from wild claims that border on insanity, and insist that any such claims are supported by certain verifiable (peer reviewable) standards?

 

It's only your opinion those reviews are "insanity" and an insulting one at that.

 

I spend very little time on HF anymore since it's become clear to me how dominated it is by this sort of idiocy. Even the headphone sections, which are of the most usefulness to me, I feel are corrupted and essentially unreliable because of the sort of nonsense prevalent in the rest of the forum.

 

How do you deal with the audio world itself? It's no different than head-fi.

post #227 of 454
Quote:
Originally Posted by mike1127 View Post

Originally Posted by badmonkey View Post

 


So why don't you take the clearly more rational choice of "freeing" the forum in general from wild claims that border on insanity, and insist that any such claims are supported by certain verifiable (peer reviewable) standards?

 

It's only your opinion those reviews are "insanity" and an insulting one at that.

 

I spend very little time on HF anymore since it's become clear to me how dominated it is by this sort of idiocy. Even the headphone sections, which are of the most usefulness to me, I feel are corrupted and essentially unreliable because of the sort of nonsense prevalent in the rest of the forum.

 

How do you deal with the audio world itself? It's no different than head-fi.


 



There are certainly claims made in this forum that woiuld appear to be a bit extreme  from the point of view of our current (ha ha) knowledge of phsyics, such as audiophile fuses, cryo treatments, magic pebbles, cable risers, green pens, CDs in freezers, teleportation tweaks and so on. When faced with such claims it is rational to ask for credible evidence for them or to want to test them in some more rigorous way. DBT is one way of testing such claims, measurements are another.

 

Measurements have the benefit that you have a solid set of criteria and you can compare things easily and you can compare measured differences against very well known paremeters of human discriminatory powers. So for instace if a cable manufacturers claims that cable A makes the bass better and you find that cable A has 0.001db less bass attenuation than Brand X you can conclude that it is not a meaningful difference. 

 

DBT has the benefit that the subject cannot fall back on their biases but must make a decision either a same/different, A =X, A=Y or a preference (but where the items tested may be A:B or A:A), i.e they must demonstrate that the items are perceptually different in a more reliable way.

 

post #228 of 454

 

Originally Posted by Uncle Erik View Post

There is very sophisticated test gear that measure values far, far below the threshhold of human hearing. Why are these tests thrown out as invalid?

 

I don't think people are arguing that test measurements are invalid. (Personally, I'm all in favor of both extensive measurements and DBT.) It's just that measurements alone are insufficient, as they can't necessarily tell us what something sounds like. Sure, we can look at frequency plots and know, for example, if the highs are rolled off, but some products might actually sound better with the highs slightly rolled off than with dead flat response.

 

And what's the sonic effect of an impedance change or digital jitter? Conversely, what do sonic descriptions like "airy soundstage" or "improved dynamics" look like on a chart? Such questions can't be answered scientifically without the use of DBT, which can serve as the link between the measurements and the perceptions.

 

To put it another way, we can't grasp the aural experience of a Beethoven symphony by staring at the notes on a sheet music page or by staring at the waveforms in audio software.

post #229 of 454



 

Quote:
Originally Posted by aimlink View Post




I don't see where anyone is throwing these tests out as invalid.  Where has this EVER been done?  What I see are skeptics considering these tests limited in scope and failing to measure all that human hearing can discern.  Tests will only give a result for what is being measured.  Conclusions can only be made about what is measured and nothing more.  Extrapolations are just that... extrapolations.  Conclusions are often unsound as well, while there's nothing wrong with the test or the results obtained.

 

Secondly, I don't see where anyone is really twisting our measurements inability to tell us everything as meaning that we don't know anything.  If you ask me, it's the reverse that's happening a lot more in that some are twisting what is known and measurable into implying that ALL is known.  IOW's, if we can't measure it after all these 80yrs. then it means that it isn't there and even if it's there, it's meaningless or insignificant.



I was reading this morning and came across this and posted it elsewhere in response to another member's question.

======================================================================================

 

DefaultPossibly the worst assumption in audio electronics

Wrong assumption -> people who study audio electronics know very little about human hearing, but assume they know more about it then they really do.

I guess I wrongly assumed most people knew this information, but then decided this must be one of the main reasons so many people have disagreements about audio electronics. Here's the great revelation. Human hearing is incredibly sensitive. Even though a lot of our hearing apparatus is mechanical it is far superior to most electronics on the market, ie. our hearing can detect more flaws in the electronics then those who parrot electronic theory realize. Its well known that real electronic components differ from theoretical electrical theory used to teach it. Of course, some people may have better hearing than other people. I read about these incredible numbers in the links below in reference to human hearing years ago.

There also seems to be a number prejudice, ie. when someone sees .1 % THD or even .01 or .001 % THD those that know nothing about human hearing assume that those numbers are so small they must be insignificant.

Read the great truths here about human hearing that most of you never knew.

Quote:
The human ear is one of the greatest marvels of nature: the inner ear or cochlea performs at least 1GFLOPS of real-time sensing, filtering, amplification, gain control, and data-compression computations in a tiny volume. The ear consumes about 14 μW of power while running on a 150mV battery; it could run on a pair of AA batteries for 15 years. The ear can sense 0.05 angstroms of eardrum motion at its best frequency and has an input dynamic range that spans 12 orders of magnitude in sound intensity. The ear operates over a frequency span of about 3 decades (10 octaves). Our ears report information with enough fidelity such that the auditory system can make a sound-location discrimination that corresponds to an inter aural time difference of a few microseconds even though the component parts of the system have 1-10 millisecond time constants. These impressive specifications were produced by at least 220 million years of evolution.
http://www.rle.mit.edu/avbs/document...NRFCOCHLEA.pdf

---------------------------------------
Quote:
How sensitive is hearing?

Extraordinarily so. The ear can detect a sound wave so small it moves the eardrum just one angstrom, 100 times less than the diameter of a hydrogen molecule. Murray Sachs, director of biomedical engineering, likes to say that if there were nothing between you and the airport, 10 miles away, and if there were no other sounds, nothing for sound to reflect from--then theoretically, you could hear a piece of chalk drop at the airport.

Johns Hopkins Magazine - September 1996 Issue

There's more examples. Just use Google.  

 

===========================================================================================

 

I found it here....  http://www.diyaudio.com/forums/lounge/171623-possibly-worst-assumption-audio-electronics.html

 

I'm not saying anything is right or wrong, I have spent time and money doing my own testing and research, and even funded other research by members here using equipment far superior to mine, I just don't sweat it all that much while I read and listen to the beautiful music.

 

I think you're right aimlink, in that measuring and knowing is far more than just magnifying something to make it visible. To me there is just far too much going on to make any standard worth considering. Too many variables. For me it's a part of listening that makes it somewhat attractive. Not knowing why.

 

post #230 of 454

 

Quote:
Originally Posted by mike1127 View Post

It's only your opinion those reviews are "insanity" and an insulting one at that.
 


Good, people that blindly believe what their delusions order, and refuse to indulge any form of rigorous testing that they could be held against, should be insulted. I have no problem with that. It is an effective social mechanism which acts in the general good.

 

The world we live in depends on that being the case in very many fields. People's health and lives depend on quacks being laughed out of the room if they propose that blood-letting is an effective treatment. Lives, and vast sums of tax-payers' resources, depend on engineers being derided and sidelined if they believe unsubstantiated things about the steel they work with to build bridges. What depends on an engineer at NASA being immediately fired amongst burning humiliation should he suggest the Earth is flat or there is only zero-G at that one point between the Earth and Moon?

 

In the audio world nothing is so serious. Except, of course, large sums of money are involved, which in its own sense is quite serious. There is something very wrong about an enthusiastic hi-fi fan being convinced he needs to spend $10,000 to feed a head-phone or speaker system, when $1,000 might obtain no detectable difference. The former is horribly socially irresponsible. What HF is doing with their "DBT free" policy is enabling and encouraging exactly that sort of thing. It is wrong.


 

Quote:
Originally Posted by digger945 View Post



 



I was reading this morning and came across this and posted it elsewhere in response to another member's question.

======================================================================================

 

DefaultPossibly the worst assumption in audio electronics

 


That's wonderful. You have found yet another example of the "golden ears" argument. So, how about those super sensitive ears demonstrate the difference for the rest of us untermensch between power cable A and B? Oh, that's right.

post #231 of 454
Quote:
Originally Posted by badmonkey View Post

 


Good, people that blindly believe what their delusions order, and refuse to indulge any form of rigorous testing that they could be held against, should be insulted. I have no problem with that. It is an effective social mechanism which acts in the general good.

 

The world we live in depends on that being the case in very many fields. People's health and lives depend on quacks being laughed out of the room if they propose that blood-letting is an effective treatment. Lives, and vast sums of tax-payers' resources, depend on engineers being derided and sidelined if they believe unsubstantiated things about the steel they work with to build bridges. What depends on an engineer at NASA being immediately fired amongst burning humiliation should he suggest the Earth is flat or there is only zero-G at that one point between the Earth and Moon?

 

In the audio world nothing is so serious. Except, of course, large sums of money are involved, which in its own sense is quite serious. There is something very wrong about an enthusiastic hi-fi fan being convinced he needs to spend $10,000 to feed a head-phone or speaker system, when $1,000 might obtain no detectable difference. The former is horribly socially irresponsible. What HF is doing with their "DBT free" policy is enabling and encouraging exactly that sort of thing. It is wrong.


 


That's wonderful. You have found yet another example of the "golden ears" argument. So, how about those super sensitive ears demonstrate the difference for the rest of us untermensch between power cable A and B? Oh, that's right.

I think you are as misguided as they come. I'd say even dangerously so.
 

post #232 of 454
.  I had better retract that!!

Edited by aimlink - 8/11/10 at 7:02am
post #233 of 454

Yes, the human ear is wonderfully sensitive yet it's also the sense which people seem to take the least care. Everyone knows to wear sunglasses yet few realize (and/or care) that they're harming their hearing at loud concerts, sporting events, noisy subways, etc.

 

It's also surprising how much human energy is spent discussing the audibility of cables. There are far greater audible differences in audio to be explored. 

post #234 of 454

And this is the actual reason why DBT is forbidden outside the science subforum, it leads to a shouting match, calm down please.

post #235 of 454

X2!
 

Quote:
Originally Posted by Donald North View Post

 

It's also surprising how much human energy is spent discussing the audibility of cables. There are far greater audible differences in audio to be explored. 

post #236 of 454

It is too bad that almost none of the proponents of dbt know anything about perceptual experimentation.   

 

I understand that many people want definitive evidence on issues in this area before they plunk  down big bigs, or even little bucks but it isn't going to happen.

 

Why?  Firstly because dbt is a generally innappropriate for audio work. It is not the method of choice in psychophysics, where people actually study auditory perception, because it is too crude.  Thus it is easy to show no differences.  Conclusions of no difference are not scientific proof of anything either because there is no difference or because the experiment is no good.  I should add that scientific journals generally will not  publish null results for these reasons.

 

Psychophysical studies are more likely to be based on instensive studies of a small number of listeners using various adjustment or constant stimuli levels.  See  http://en.wikipedia.org/wiki/PsychophysicsThe typical, "I got a bunch of my buddies over and gave them a few random trials just doesn't hack it." 

 

I also fail to see why so few dbt types fail to grasp that the issue is not just about cables.  No-one does dbt on the difference between a $5K headphone and a $10.00 headphone to determine if its supposed virtues are not just hype.

 

The reality of audio is that for a variety of reasons, including the difficulty of getting valid objective data or even agreement of what one should be measuring,  it is a subjective enterprise.

 

I give most weight to what I personally hear, followed by the reports of those persons whom I think know what they are talking about.

 

In order to get decent personal knowledge you need to go to the meets that are regularly set up by this site. There you will quickly find out what is or is not good sounding.

 

I went to the LA meet last year and I didn't see anyone demonstrating the virtues of using soldered paperclips instead of cables. (I would have loved to have seen this though.)  Rather I saw a lot of expensive equipment including cables. People were bringing their own music for testing and   and swapping their own equipment in and out of other systems.

 

This is what the field is about, dbt debates are just jerking off.

 

 

 

 

 

 

 

 

post #237 of 454
Quote:
Originally Posted by edstrelow View Post

This is what the field is about, dbt debates are just jerking off.

 


I don't entirely agree with you, but this is why I want to conduct tests where people review strings of paperclips soldered together in addition to whatever other cables they choose to listen to.  I have a terrible feeling that soldered paperclips, a cable with a resistor slipped into one channel and not the other, cables brined in seawater for a few weeks, and so on, will get high marks as "good" cables.

 

Also, how do you explain that even the most sophisticated test gear reveals no difference between cables?

 

Is there something fundamentally wrong with our understanding of physics?

post #238 of 454

there's lots of stuff that physics has no explanation for.  i.e. ball lightning.

post #239 of 454
Quote:
Originally Posted by Uncle Erik View Post

Is there something fundamentally wrong with our understanding of physics?


My suspicion on this is that there's more to it and that it's not simply a matter of what we already know and understand being rubbish or poorly understood.

 

I'm not hearing differences between USB and optical outputs on my iMac when playing redbook CD's in lossless format.  I just got a modded HiFace and no difference still despite the positive testimony about it.  I am yet to hear a consistent difference between 320Kbps and lossless formats.

 

OTOH, I do hear a difference using a Cardas Cable with my HD800's as opposed to the stock cable.  

 

My bias seems quite selective since this seems to be about bias. 

 

Anyway.... we'll have to see.

 

Edstrelow..... interesting post since it's corroborating some of my concerns that my technical knowledge base cannot fully substantiate.  I'd love to read a sane and civil discussion about this with you as a participant.

 

Would you be able to expand on exactly why a DBT is inappropriate for proving audible differences between audio gear?  You say it's crude... any details on this.

 

And I've LONG ago been waving in the breeze that the bigger cash cow belongs in the domain of amps, cans and other gear that claim improvements etc that are potentially way overhyped.  For instance, I was just reading a discussion on SE vs Balanced amp'ing.  It would seem that the virtues of an investment on Balanced amp'ing isn't so clear.  That amounts to significantly more than a cable upgrade.  There's my HiFace as well vs USB.  There's so much more but no-one says anything because there's a measurable difference.  No-one can really say anything because they can't prove that a measurable difference isn't really audible and even if so, is genuinely meaningful.  So in frustration, the cables issue becomes a punching bag it would seem.  So much emotion and over a relatively small area of expenditure in the audio chain.


Edited by aimlink - 8/12/10 at 2:52pm
post #240 of 454
Quote:
Originally Posted by aimlink View Post




My suspicion on this is that there's more to it and that it's not simply a matter of what we already know and understand being rubbish or poorly understood.


And I've LONG ago been waving in the breeze that the bigger cash cow belongs in the domain of amps, cans and other gear that claim improvements etc that are potentially way overhyped.  For instance, I was just reading a discussion on SE vs Balanced amp'ing.  It would seem that the virtues of an investment on Balanced amp'ing isn't so clear.  That amounts to significantly more than a cable upgrade.  There's my HiFace as well vs USB.  There's so much more but no-one says anything because there's a measurable difference.  No-one can really say anything because they can't prove that a measurable difference isn't really audible and even if so, is genuinely meaningful.  So in frustration, the cables issue becomes a punching bag it would seem.  So much emotion and over a relatively small area of expenditure in the audio chain.


It's easy to say that there are things we don't understand, but have you thought through the implications?  From what we know, there are three electrical characteristics that affect cables: inductance, resistance and capacitance.  All three can be measured very, very precisely.  These tests can be repeated by anyone anywhere with a wide variety of different test equipment and get the same results.

 

You're suggesting that there is a fourth force that acts on an electrical signal.

 

This fourth force could  not have any effect whatsoever on inductance, capacitance and resistance.  Otherwise, measurements of those three would be off a bit here and there.  But that doesn't happen.  If they were off and no one knew why, then, yes, I could see the possibility of a fourth force.  But it's remarkable that the proposed fourth force has absolutely no effect whatsoever on the three known forces.  Even more remarkable, since the three known forces are closely connected.  Changing one changes the others.  But the new one must operate independently.

 

Further, the fourth force would have to modify the signal somehow in a way that does not appear on an oscilloscope or spectrum analyzer.  If you contend that a cable changes the electrical properties of a signal, then why does the change not appear in a visual representation of the waveform?  These devices are very sophisticated and can measure the tiniest of changes.  So if the signal changes, why doesn't it show up?

 

It's pretty amazing that there's a force that changes a signal without showing any change to the signal, and all the while having zero effect on capacitance, inductance and resistance.

 

It is also amazing that this fourth force only shows up in audio.  There are lots of other electrical devices out there, but they all seem to behave according to known laws.  These debates only take place in audio.  You never see these claims for video.  Nor do you see them for test equipment, hospital devices, refrigerators, lights, or anything else.  You don't find them in radio applications, either, and those are much more complex than audio devices.  If cables work in audio, then why don't they work on anything else?

 

Like I said, the possibility is out there, but it would mean a fundamental change in physics.  It's Nobel Prize territory.

 

And what floors me is that this mysterious reinterpretation of science is done by some guy working out of his garage charging a 10,000% markup.

 

As for amps, have you ever gone through how much the parts cost?  Go over to Headwize and price out the components.  If you want good quality parts and good circuit design, it's easy to put down $500 in parts.  Labor, overhead and profit are just like any other manufacturing company.  Amps are complex and take quite a few hours to build.  Believe it or not, but the margins in the amp sector are probably the thinnest in audio.

 

The debate doesn't go on with amps because they produce actual measurements.  Maybe you're right about the audibility of differences, but there are practical applications like needing Watts for inefficient speakers that an 8W 300B amp just won't drive.


Edited by Uncle Erik - 8/12/10 at 5:49pm
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