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In Reply to: RE: DBT or not DBT posted by Ozzie on December 02, 2014 at 19:07:52
How results of a test - double or single, blind or sighted, doesn't matter at all - achieved by persons A,B,C,D,E and F using audio system X, pertain to person G, using audio system Y? To be even more pedantic, X and Y here are system/room combinations, not just systems.
Unless we're talking about a particular person's test results, applied ONLY to that person and his audio system, all this "DBT" rhetoric is pure, unadulterated nonsense - one of the most egregious examples being infamous Meyer-Moran "CD vs. Hi-Rez" so-called "test".
To exaggregate a bit (just a bit) - why not fill a room with a bunch of deaf blind monkeys, ask them to listen to CD and hi-rez recordings through AM radio, and declare the results an ultimate truth?
Follow Ups:
That kind of test is only useful if you have posed the right question and if you understand more about how our sense of hearing works.
Our hearing is NOT like a measurement microphone which is ideally a faithful conversion of the pressure at the mic diaphragm to a proportional voltage. Hearing as we know it is a learned process AND involves not only what we have learned through our lives but also what we see and know. A “blind test” or more correctly I think, a test where you compare two things but don’t know which is which at the time is a way to separate what you see and think from what is entering your ears in terms of sound pressure.
Snipped from;
http://www.audioasylum.com/forums/critics/messages/7/77300.html
Sounds crazy but it's true, in fact our sight can completely over ride what we hear (google and watch the mcgurke effect) and what we know can shape what we hear as well.
So, when you have your hearing tested, they limit the stimulus to one domain, your auditor channels, there is no red light that goes on with the tones, if there was one, your hearing would be much better, the person running the test can't give you any clues, if he winked or you saw him press a button. Your hearing would be much better, even if you weren't consciously aware of seeing it. So in the hearing test, it all depends on what your ears alone can detect.
Just like with wine conisures some hifi enthusiasts have an extraordinarily high opinion of their own capabilities and are very proud (and welcome any suggestion along this line, like a country welcomes an asteroid strike).
In scientific testing methodology, for some things blind testing is the norm however. It is the only or at least best way to minimize bias .
To be scientifically rigorous, one must follow all the rules and protocols and use the appropriate math for analysis. To satisfy the nth degree of precision, is far outside of what is done in hifi. In fact, I am not sure people generally understand there is a connection between what we see, know and expect and what we hear but it is an overriding principal too. We also interpret anything new based on what we already know and understand.
To break the connection between what you know, expect or see and what you actually hear (by hear I mean the air pressure changes entering your ears, all one needs is to arrange a situation where you compare two things without knowing or seeing which was which.
In an informal test like this, do this when you're comfortable with music you have selected at your leisure and usually with a silent friends help (or use a SBX relay box etc), go back and forth between A and B where you don't know which is which. When you find musical snippets where you hear differences and then just go back and forth with those snippets.
Often, people find what they had previously heard as a large difference in sighted comparisons becomes a smaller one, once "the knowledge of which one was which" is removed as then your judgment is only based on what reaches your ears.
Do this A VS B comparison as often as you want, whenever you want until you are sure of your conclusion. The two sound different, the same or a little different.
I think the reason some don't like the idea is because that pretty often, once one has heard the big difference disappear, the magic of it usually doesn't return. The up side for the diy'r is, if you have just made something that does sound better when compared “without knowledge”, it is likely to sound better to most everyone else too even when they also don't know what it is. The up side for the buyer is that one can be “primed” to “hear something special” but if it goes away after a bt, then it was not part of what was reaching your ears but if it was you found something transferable to others.
So, DBT tests are only useful to compare two things and while a great deal of protocol is required to do a valid test scientifically speaking like for a new drug etc, the actual strength of the test in hifi is simply that it forces the listener to depend entirely on their ears and cuts out what you know, see and expect which we are unaware of , is also part of our “hearing process”.
They are much more useful at the engineering stage or for the diy'r as they are more likely to be comparing two things / components etc and rarely would a buyer be able to set up such a test and the marketing agents are generally against comparisons like that.
I think you are saying that it's common to stop hearing differences under normal sighted listening conditions after conducting a blind test. But what if you don't? I don't know whether this is typical, but my personal experience has been that differences tend to vanish after repeated A/B comparisons, whether sighted or blind, and then reappear once I'm back to regular casual listening.
Power cables are a good example. As an engineer with a physics background and MSEE, it pisses me off that power cables seem to make a difference on some of the components I've used in my systems. I once conducted a single blind test with the help of my patient wife, and as the test progressed, I got less and less confident of my answers, and the result was null. I also noticed the same effect under sighted conditions: after switching cables back and forth several times over a couple hours, I couldn't hear a consistent difference anymore. But after a few days and and a few casual listening sessions with no changes (to reset my reference point), the differences came right back. I've repeated the comparisons a few times over the years when changing gear. Whenever I think I hear differences between cables, they will vanish during repeated A/B switching under sighted conditions, but they are apparent again in "normal" casual listening over the course of multiple days and several listening sessions.
So what can I do? On one hand, I could forget about power cables and live with a system that doesn't quite give me the same level of satisfaction, and pat myself on the back for sticking to my engineering principles and feel smug that I've 'conquered' the placebo effect. On the other hand, I can continue to mess around with power cords if they make my system sound more satisfying, and live with the fact that I can't prove it to anyone and don't understand why they make a difference. I chose the latter, because even though the difference to me is small, it is meaningful, and I have a preference, and it's something I can't "un-hear" regardless of the accumulating number of failed cable DBTs.
What would you do?
I suggest people buy equipment they like, equipment they prefer. There is no need to follow the results of DBTs (which actually may not narrow down the choices very much!) unless you want to.
-----
"A fool and his money are soon parted." --- Thomas Tusser
But in this case, I actually wanted to stop hearing a difference!
If you don't know "which is which" but you can hear one is different, then, you have established that the difference you hear IS due to what is entering your ears alone.
Anyway, I was responding to your suggestion that "once one has heard the big difference disappear, the magic of it usually doesn't return".
In my case, I can make the difference disappear under sighted conditions just by switching back and forth several times over a few hours.
But it always seems to come back under regular listening.
So if you're suggesting that taking a blind test can somehow make an audiophile "un-hear" something, that hasn't been my personal experience.
Oh, the "we all hear different" notion!
Might as well close the books on audio and audio discussions right?
What is the point of wasting time on communicating the incommunicable?
I am certain that you will not be capable of understanding the enormity of what you are saying.
Suppose Dave says that SACDs sound better than CDs in his system, and in particular there's this hybrid SACD where both the SACD and CD layers were equivalently mastered, and it's really easy to hear the superiority of SACD on track 1. Now suppose Brad says that he's listened to SACDs before, including this one, and he can't hear a difference between the SACD and an equivalently mastered CD. Who is right? They both are - they simply hear what they hear.
Now imagine there are 100 DBTs conducted involving 1000 different audiophiles using high end and some SOTA systems, where the protocol was chosen to be as sensitive as possible. And the results of all 100 tests are null. Do you think Dave is suddenly going to stop hearing that improvement in the SACD layer over the CD layer? Do you think Dave is going to be able to successfully talk himself out of hearing the difference and stop buying SACDs, or that he would even want to?
Conversely, suppose one or more of the DBTs has a statistically significant positive result, and others are able to duplicate the positive results with the same protocol. Is Brad going to suddently start hearing a difference where previously he could not? Is he going to start buying SACDs anyway even though he doesn't hear a difference, just because a blind test demonstrated that some other people could hear it?
DBTs in audio are conducted to win arguments.
...not really because no one ever wins, but perhaps to make the pro-DBTer feel superior using a pseudoscientific method to find out he doesn't hear differences.And to justify owning his cheap mid-fi rig.
Edits: 12/07/14
nt
remains strong today. :)
Is that the Atkinson "all DBTs produce nulls, I hear a difference, so DBTs can't be right "argument" " dressed up in different garb?
Atkinson has a good handle on the situation. He understands the Duck Test. (When I hear the duck quack, I don't need some anonymous Internet asshole calling me delusional.)
Not all DBTs produce nulls. However, when they don't the "objectivists" ignore the results. They cry "fraud" and "experimental error". If you want to understand how this works, you can read Thomas Kuhn.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Certainly some DBTs have positive results. E. Brad Meyer did tests many years ago in which the results were that a tube amplifier and a solid state amplifier sounded different. Stereophile did a poorly run blind test between a tube and a SS amp and got a positive result, and later, a university prof did a better run DBT with the same kinds of amps and got a much more definite positive result. Indeed, in amplifier reviews, Stereophile publishes a graph showing the frequency response into a simulated speaker load. Many tube amps have a high output impedance, and so into many speaker loads they do not have a very flat FR.
Determining whether there was an experimental error and trying to see if the results can be replicated are part of scientific method.
-----
"A fool and his money are soon parted." --- Thomas Tusser
...this requires a number of things:
1. everything be controlled except the *one thing* being tested for
2. sufficient number of subjects so that the subjects' critical listening skills or lack thereof are controlled for
3. sufficient number of trials to reach a significant confidence level the results are accurate
What part of the *scientific method* don't you understand?
Are you seriously saying that one cannot perform scientific tests on an individual basis? GMAB
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"A fool and his money are soon parted." --- Thomas Tusser
"Are you seriously saying that one cannot perform scientific tests on an individual basis? GMAB"
The answer to your question differs according to the definition of "scientific".
Science is a method, Science is a social activity. Science is the established religion of many countries ("scientific materialism").
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
...sure - that only apply to that individual and are not very scientific.
It doesn't have to be, or probably isn't, "science" just to control your own expectation bias.
If it's real science, though, let's see you get one of those published in a scientific journal.
Nonsense. Scientific tests are done very often on individuals. Just some examples. Police can examine the DNA of a person and compare it with DNA left in a crime scene or otherwise connected with a crime. Doctors can have lab tests done on patients' blood samples and find all sorts of things.
Or, people can do audio DBTs to see if they can detect the so-called "sonic signature" of an amp and numerous other things.
-----
"A fool and his money are soon parted." --- Thomas Tusser
..the first two examples are actual science since they've been validated - proven to provide valid results and aren't influenced by the subject.Your personal DBT may give you different results at different times during the day, depending on your mood, whether you have water in your ears, tinnitis, different ancillary equipment used, etc.
Not well controlled or very scientific, but a technique some find useful.
Edits: 12/09/14
"Your personal DBT may give you different results at different times during the day, depending on your mood, whether you have water in your ears, tinnitis, different ancillary equipment used, etc."
That, of course, goes in spades for subjective auditioning or any kind of listening. Reviewers are not immune.
"Not well controlled or very scientific, but a technique some find useful."
You have not established that personal DBTs cannot be scientific.
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"A fool and his money are soon parted." --- Thomas Tusser
> That, of course, goes in spades for subjective auditioning or any kind of listening. Reviewers are not immune.>
Straw horse.
> You have not established that personal DBTs cannot be scientific.>
Until you show a method for controlling all of the variables, including the ones I mentioned above, you have not shown how it is scientifically valid.
"Your personal DBT may give you different results at different times during the day, depending on your mood, whether you have water in your ears, tinnitis, different ancillary equipment used, etc."
If one can establish one hears a difference under the conditions of the audition, than that is established with some degree of probability. Pointing out that sighted auditions are affected by even more things is hardly a straw man.
Merely getting positive results on DBTs does not necessarily indicate just what the differences heard are.
How would you establish that all conditions are controlled in any test? How do you know something was not missed? You can't be absolutely certain of that. You can only remove known variables, and finding things that affect the results is part of science.
If you use different ancillary equipment, that would be a different test because another variable has been introduced.
-----
"A fool and his money are soon parted." --- Thomas Tusser
Determining whether there was an experimental error and trying to see if the results can be replicated are part of scientific method.
There is not a single test using the bogus ABX box that tests its effect in the signal chain prior to its use in a test. Real science calls that a "control". All you find is a series of assumptions about the contact resistance, etc. that COMPLETELY miss the point!
Pseudo science at its best. :)
In the recent positive DB tests, the physical switch box has been replaced by software that selects between playback of two audio files. In this case if the two files are in the same format then the only difference between the sounds produced comes from differences in the files themselves. There is no sonic degradation from the test jig. So in this case there are adequate controls against losing the ability to hear audible differences. Ironically this software has glitches that work in the opposite way, take inaudible differences and make them easy to hear. A good example is a tiny (sub millisecond) time shift between the two files coupled with the ability to play arbitrary clips in the files. I know this for a fact, because once I observed this going on I was able to easily exploit this weakness and to hear differences that would otherwise have been difficult.
The people building this ABX hardware and ABX software have shown themselves to be adequate novelty toy makers, but not proper experimental scientists.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
> Not all DBTs produce nulls. However, when they don't the "objectivists"
> ignore the results. They cry "fraud" and "experimental error". If you want
> to understand how this works, you can read Thomas Kuhn.
Or the Hydrogen Audio thread linked below.
John Atkinson
Editor, Stereophile
I should have said "why this works" and not "how this works". As you pointed out the thread shows how this works.
What I can not fathom is why reasonable people, such as you and Amir, devote effort to debunking these people, who are at best fools. Perhaps there is some kind of a market-oriented conspiracy, but if that is so I can not fathom why people would be conspiring to perpetuate a 30 year old technology that was already known to be sub-standard at the time it came on the market. More likely it is a bunch of sick people suffering from personality disorders or worse.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
You're a funny guy, Tony. Why just last Saturday, I hosted an event for 11 audio enthusiasts entitled, "Building on the Right Foundation - Part 4 - Redbook CD - Perfect Sound Forever?"Based on the posted feedback from that event, I'd venture that I was able to successfully demonstrate:
1. That the Redbook CD format had been unduly beaten to a pulp for at least the past 10 years.
2. That the Redbook CD format contains volumes more audible music information embedded within than anybody previously thought possible.
3. That whether or not the early promoters and pioneers knew it, the Redbook format was and is wholly sufficient for the entire music industry, including the "high-end" audio sector.
4. That the format (at least Redbook) has nothing whatsover to do with the serious performance limitations found in essentially every last playback system.
Oh, and for what it's worth, I demonstrated all this:
1. On a 2-component, 2-ch. playback system and a pair of VMPS RM40 speakers.
2. With the 2 components retailing for under $4000.
3. Included songs from artists like Dianna Ross and the Supremes, Lou Reed and record labels like Windham Hill. Regrettably, time did not permit me to play songs from The Tokens, Frank Sinatra, Herman's Hermits, or The Associations.
Nowhere did I claim that Redbook CD format was perfect as that's a bit of a reach for anything. But what I did claim and hopefully demonstrated was that unbeknownest to the early promoters (and obviously many of you), the Redbook CD format was and is more than than musically sufficient for even the high-end audio industry and that, contrary to conventional wisdom, their slogan actually contained very little hype after all.
The point being, Tony, is that you are incorrect in your statements about Redbook CD format being substandard.
What you (and others) are really confessing to when making such statements is that, regardless of format, it is your own playback system's level of musicality that is grossly substandard. Simply because your system is so distorted that much of the music info embedded in the recording (regardless of format), though processed, remains inaudible below a much raised noise floor.
Edits: 12/14/14 12/14/14 12/14/14
You're kidding, right?
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Guys like you always seem so busy chasing windmills, I wish I were.
AJinFLA used to post here until he was banned (given his charming social skills). I confess that his level of paranoia is up there with the best.I am thankful for his "Audiphile Repellent" post which backfired in multiple respects:
1. I bettered his results.
2. Subsequently, there wasn't a single proponent of ongoing mediocrity (Pat D, BassNut Greene, The Audio Hobby, et. al.) who took up my invitation to do same.
No takers . So predictable for the objectivist camp! :)
edit: I found sone of my favorite of Pat's posts in the series of absurd responses. Here is my reply . :)
Edits: 12/07/14
I am not aware that any of those mentioned denied that training is needed to detect very small differences. It may be that you and HP learned to detect a lot of small sonic differences. So you might be able to detect small differences in sound better than others in a DBT.
On the other hand, I see no reason to believe you or numerous reviewers who say they detect sonic differences in accurate amplifiers.
-----
"A fool and his money are soon parted." --- Thomas Tusser
So you might be able to detect small differences in sound better than others in a DBT.Along with legions of other discerning music lovers worldwide.
On the other hand, I see no reason to believe you or numerous reviewers who say they detect sonic differences in accurate amplifiers.
Of course you don't. What is *your* definition of an "accurate" amplifier? edit: Perhaps you might provide a couple of examples. And since your link requires car amplifiers , is that also part of your criteria?
As for you link, it is yet another crippled-from-the-outset parlor trick requiring the use of a box that immediately invalidates the results by combining the output content.
Magicians (remember "The Amazing Randy"?) require they must control the trick for the intended outcome. :)
Edits: 12/09/14 12/09/14
You evidently did not bother read the link very carefully.
E-Stat:
"And since your link requires car amplifiers , is that also part of your criteria?"
Richard Clark:
"NOTE 1 (from conditions 2 & 7) This test mentions 12v and "car" amps only. The test originally began with home/studio type amps and was revised in 1994 for the car audio industry. This version dated 2005 is again expanded to include 120 Volt home/studio/commercial type amps."
You may make baseless claims about a switching device all you want, but if you want a really invalid test, it is a sighted audition, where you can identify the different amplifiers before playing anything, before even turning them on!
If you don't want to use an ABX switcher, then don't.
Somehow, you offer no reason to give any credence to reviewers who claim to hear differences between accurate amplifiers and other electronics by doing sighted auditions.
Of course, using different pieces of equipment is often a good way to form preferences.
Accurate amplifiers would be those that have flaws below known thresholds of hearing.
I think what really gets the goat of many people is that some of us simply don't believe they can hear everything they say they can.
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"A fool and his money are soon parted." --- Thomas Tusser
...show it to us and the measurements to prove its accuracy.
That's easy enough.
http://www.stereophile.com/content/bryston-7b-sstsup2sup-monoblock-power-amplifier-measurements
http://www.soundstagemagazine.com/measurements/bryston_4b_sst/
http://www.soundstagemagazine.com/measurements/simaudio_moon_w6/
-----
"A fool and his money are soon parted." --- Thomas Tusser
Looking at the Bryston, it does not measure to be a straight wire with gain to the limits of the measurement equipment used. This is objective evidence that the amplifier is not "accurate".
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Nothing of human manufacture is absolutely perfect. However, the deviations in the frequency response of the Bryston 7B SST2 appear to be inaudible in normal high fidelity use, including the frequency response into the simulated speaker load. It seems to be well within the ABX Matching Requirements:
http://djcarlst.provide.net/abx_crit.htm
John Atkinson wrote:
"The Bryston's output impedance was low for a balanced design, at 0.11 ohm at low and middle frequencies, rising slightly to 0.17 ohm at 20kHz. As a result, the modification of the amplifier's frequency response due to the Ohm's Law interaction between its source impedance and that of the speaker will be small. With our simulated loudspeaker, the variations in response remained within ±0.1dB limits (fig.1, gray trace). The amplifier's response into 8 ohms didn't reach –3dB until almost 200kHz (fig.1, blue), which correlates with the well-defined 10kHz squarewave response (fig.2). The 7B SST2's output does start to fall slightly above 10kHz into lower impedances; into 2 ohms (fig.1, red), the output at 20kHz is down 0.4dB, though this will have no subjective consequences."
-----
"A fool and his money are soon parted." --- Thomas Tusser
I saw no perfection in the amplifier measured by JA. One can not conclude from measurements that a piece of gear sounds good. One has to listen to a system containing the device in question. One is still at risk of reaching the wrong conclusions as to the cause of what one heard. The measurements were far from perfect, as JA's equipment was showed.
If you want to convince me by measurements that an amplifier is transparent then I will have to be able to pick the source material. I will conduct a null test, comparing the actual output vs. the "correct" output. If the null tests shows that the error was -160 dB below the correct output measured with a 200 kHz bandwidth, then I might be convinced by measurements. (You will be responsible for providing the accurate test equipment. It might be available from the appropriate sources. I suggest going to the experimental physcists at CERN. They might be able to help you. I am talking far beyond Audio Precision. Test equipment needs to be 10x better than the device under test, and this is difficult with audio, where high end equipment is already at the state of the art.)
In the absence, I will just go with my ears. Why am I right and you are wrong? Because we are talking about audio amplifiers intended for listening to music, not laboratory instruments intended for conducting measurements.
As to perfection: "God made the integers, all else is the work of man."
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Did anyone tell you not to buy the amplifier you prefer? Certainly not me. In fact, I suggest people buy the equipment they prefer.
-----
"A fool and his money are soon parted." --- Thomas Tusser
Do you, by any chance, print your suggestions on toilet paper, too? Because that way, they could really be put to their intended use...
Because we are talking about audio amplifiers intended for listening to music, not laboratory instruments intended for conducting measurements.
You'll never convince the deaf who lack exposure to better gear and don't have the foggiest notion of what you're talking about. :)
Yes, I agree. Useless to try and convince the willful deaf.
One minor point of disagreement. One does not need exposure to better gear if one has access to the real reference. One can do this if one makes live recordings, or one can guess what one should be hearing if one listens to live acoustic musical performances. People who listen only to commercial studio recordings and amplified concerts can not possibly have a basis on which to judge sound quality. But then, does this matter? Today it's called "high end". It used to be called "high fidelity". Big difference between high price and high quality.
Maybe you will enjoy my recent post.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
One does not need exposure to better gear if one has access to the real reference.
That is my sonic goal as well. While I do regularly attend live concerts and enjoy listening to wifey play her baby grand, the majority of music I listen to is from commercial recordings. Having a ready reference of what any given recording can do provides a useful reference for comparisons.
I've been enjoying rediscovering my library following a recent preamplifier upgrade. I live to hear deeper into my favorite recordings.
Your linked story and background illustrates to me the only real way to compare various recording types. If Meyer and Moron compared live feeds at 16/44 vs 24/192 instead of using their Rube Goldberg approach, I suspect even they would have been convinced that Redbook is anything but "Perfect Sound". Over at AR, there's a Disney engineer who works largely with multi-channel soundtracks who likewise uses live feeds for determining recording quality all the way to up the DXD master.
The part in your story about having to really force the issue of worn cartridges with the subhumans was funny!
The sub humans are still around, but they tend to hang out on other audio forums.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
...I have listened to is the Bryston 4B-SST and I thought it sounded terrible - cold, dry and clinical but with excellent bass slam.
Real music does not sound like that.
"If it measures good, but sounds bad, you're measuring the wrong things."
How do you know that this wasn't what was recorded? The amplifier is just one component in a long chain from microphone to loudspeaker. Or perhaps your preferred amplifier interacted with the speakers and listening room in a more felicitous fashion.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
...listen to amps with more than one speaker which is the component that matters most with amps.And I listen to numerous recordings I am familiar with when evaluating a component.
Others report the same sonic signature with this amp.
Have you heard it?
Edits: 12/12/14
Accuracy to exactly what?
> Accurate amplifiers would be those that have flaws below known thresholds of hearing.>
Looking at the measurements he provided, I would guess that because the harmonic distortion is very low, he thinks the amp is accurate.
Obviously there is more to reproducing music than that...
sine waves - given that's how they're measured. :)
JA performs a number of different measurements on the Bryston 7B SST2, including a square wave measurement.
As for the inadequacy of using sine wave for measurements, you are whistling in the wind as far as I can tell.
-----
"A fool and his money are soon parted." --- Thomas Tusser
(nt)
E-stat complained about measurements made with sine waves, though without a shred of evidence that would invalidate the measurements. I pointed out the JA provides a square wave response, illustrated by his measurements for the Bryston 7B SST2, mentioned above.
So you think the 4B SST2 would not similarly have a good square wave response? That can be predicted by the FR measurements as JA remarked in his review of the 7B SST2. Look at Chart 1 from the Soundstage BHK Labs measurements of the 4B SST2: less than 2 dB down at 200 kHz.
I have never heard the alleged hardness of Bryston amplifiers. Many thousands who buy them seem to like them. Now, if you or Michael Fremer showed you could detect the hardness in controlled DBTs, that would give some credibility to your claim. That's one reason I don't give subjective reviewers much credibility when they talk about the sound of accurate electronics.
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"A fool and his money are soon parted." --- Thomas Tusser
...if two independent audiophiles whose ears I respect describe the same sonic signature to an amplifier that I hear, then it is an accurate assessment.
If you can't hear it, I'm not surprised.
In my own experience, I find DBTs to be pseudoscientific and worthless with audio equipment but scientifically valid for the new drug clinical trials in which I've participated.
You can use any method you like to select your equipment as long as you don't proselytize about it to the rest of us.
For some, ignorance of the truth is bliss.
"You can use any method you like to select your equipment as long as you don't proselytize about it to the rest of us."
Oh, I see! You can proselytize but I can't. Subjectivists can say anything they like, but it's not fair to be skeptical. Sure, sure.
On the other hand, you seem to think I proselytize about how to select equipment. How do I do that? I suggest people buy equipment they like. How is that proselytizing?
-----
"A fool and his money are soon parted." --- Thomas Tusser
Simple, you would think. Okay, since we know that there will be no converts, why can't everyone retreat to their respective corners, leer at reach other and go on with their own business...and perhaps, even enjoy music?
JA performs a number of different measurements on the Bryston 7B SST2, including a square wave measurement.
Yeah, that tells us absolutely everything about the performance envelope, doesn't it? LOL! It does, however, rule out switching amps since you always see considerable "fuzz" on their plots.
As for the inadequacy of using sine wave for measurements, you are whistling in the wind as far as I can tell.
And we already know you can't *tell* very far. I really don't understand such a persistent reliance upon such sketchy and incomplete metrics. At the expense of confusing the issue with facts, let's revisit what JA says about the "scope" of measurements with the review of the Ayre KX-R Twenty line stage:
All of the first-order sonic attributes—frequency balance, linearity, lack of coloration, etc.—are beyond reproach, which means one needs to focus on such higher-order qualities as the presentation of the soundstage and the accuracy of the imaging, neither of which can be measured.
You may make baseless claims about a switching device all you want
I refer to measured results of combined feedback loop content - and the utter lack of the establishment of any controls regarding their use. No one has ever done that. Pseudo science.
Accurate amplifiers would be those that have flaws below known thresholds of hearing.
None such exists. All amplifiers are audibly flawed in one way or another. Pick your poison and budget!
I think what really gets the goat of many people is that some of us simply don't believe they can hear everything they say they can.
I only speak for my experience, but you may wave your hands as much as you like. The rest of us just shake our heads and smile. :)
"All amplifiers are audibly flawed in one way or another."
Ah! At last a positive statement. I am sure that under some conditions one could find some audible flaws in many amplifiers, but are they the conditions under which audiophiles and reviewers actually listen to music?
I notice in your remarks about "measured results of combined feedback loop content" you neglect to provide any references or anything to show this problem exists in ABX comparators. I recall that there was a dicussion about this years ago but I have no time to try to find it. I did find someone, moniker Alón, who had talked to Frank van Alstine about the ABX comparator.
"In my conversations with Frank Van Alstine about the ABX box, he assured me that the “added component in the signal path” issue was addressed in the design of the ABX Comparator – and that sonically, it was completely transparent in their in-house listening tests."
http://sanfranciscoaudiophilesociety.com/abx-comparator-event/
In his 2005 debate with John Atkinson, Arny Krueger said something to the effect that if they set up a string of good amplifiers, damping down the output to feed the inputs of the successive amplifiers, after four or five steps, there were audible differences. You could find a link to the an MP3 file of the debate in Jacob Victor Serinus article on it.
http://www.stereophile.com/news/050905debate/
As I have pointed out that there is no reason believe that reviewers can actually detect all the differences in equipment they say they can. I have focused on amplifiers. There is an ambiguity in English here. Just because I do not believe you, other audiophiles, and many reviewers can detect many of the differences you say you do, does not mean that I believe you can not hear those difference. Technically, I am agnostic on that issue. You can call that hand waving, if you wish, but I think it is based on a misunderstanding. It is quite obvious to me that many here just feel insulted that sometimes I don't believe them.
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"A fool and his money are soon parted." --- Thomas Tusser
Ah! At last a positive statement.
That's been my observation for over forty years. Positive in what way?
I am sure that under some conditions one could find some audible flaws in many amplifiers, but are they the conditions under which audiophiles and reviewers actually listen to music?
It's called "playing the system with familiar content", Pat. I've yet to experience a perfect amplifier. Have you?
I recall that there was a dicussion about this years ago but I have no time to try to find it.
Yes, apparently you don't remember discussing this four years ago . FVA tested a box in the 2006 timeframe. All Tom offered in response was theory and speculation.
I did find someone, moniker Alón, who had talked to Frank van Alstine about the ABX comparator.
Fast forward eight years later to a newly designed comparator that unlike the switch and relay boxes used by Gow, Clark, Krueger, Meyer and Moron, etc., this is an active box that buffers the connections and apparently eliminates the overt signal mixing of the original boxes.
It will be interesting to see what comes of that comparator. While your link to his blog requested amps to be tested, I couldn't find anywhere on that site that any tests had actually be conducted. If and when results using that new box is ever published, it should be interesting to view their system and amp choices.
Do you expect what John hears to change after another DBT produces a null result? How is that supposed to happen?
Similarly, if you don't hear a difference between CD and hi-res, do you expect that to change if somebody else gets a positive result in a DBT? How would that happen?
So what exactly is the point of doing all these DBTs to prove or disprove the audibility of things? I can understand Harman's use of blind testing to try to understand listener preferences regarding loudspeaker response. I can even somewhat understand how DBTs helped codec developers figure out how to optimize the use of limited bitrate. But I don't understand the point of conducting DBTs in the hope of proving or disproving the audibility of things like cables or hi-res digital. What do you get out of that besides fodder for more internet arguments?
... and you can still be sure it goes right over the heads of true DBT believers.
Did I just go back in time? And move from Critics to PropHead?
This is eerie! :)
The sense of déjà vu is reinforced by the lack of anything even remotely novel, and that applies to all, regardless what side of the "debate" they fall on ... quintessential circle jerk.
I wonder if there has been any DBT debate, argued by any group of folks at any time in any location, that has changed a single mind.
If so, I would guess it's been extremely rare.
Actually, that would be me. Years ago, I thought that audio reviewers knew what they were talking about when they attributed audible differences to various pieces of electronics. Then some of the audio clubs showed that despite the fact that many people thought they could generally hear audible differences between amplifiers, it turned out that in blind listining tests they no longer could identify many of the differences they thought they could.
No one, not even Richard Clark, thinks that every amplifier sounds the same. If they do not sound the same, one looks for the reasons in parameters such as level, frequency response, noise levels, possibly distortion levels, polarity inversion. When those differences are removed [reduced below audible levels), it seems people have great difficulty in showing they can hear those differences in a blind test.
-----
"A fool and his money are soon parted." --- Thomas Tusser
Although I said it was rare, not impossible.So taking your reasoning above, you were convinced based on the results of various DBT's. And yet, a thinking person such as yourself would be someone I would guess would not blindly (heh! sorry...) accept such results without some research into the validity of DBT's, particularly those that use the ABX Comparator. Not to mention the problems associated with quick snippets of music vs long term exposure.
In other words, how do you know you were not duped by a magic trick (Hey kids, watch me make sonic differences disappear!)? And I'm not baiting you - I'm truly interested... and I think others would be as well. You might be the novel approach that's needed to spice up this debate. Shoot, I thought people just fell into their side but it sounds like you were either pushed or you jumped to the other.
Edits: 12/09/14
The equipment reviewers at Stereo Review and I believe, High Fidelity, also became convinced that a lot of differences they thought they identified with sighted listening disappeared with level-matched blind listening. There are many others. I am not alone in this, by any means.
In his debate with John Atkinson, Arny Krueger notes that training will increase the ability of a person to detect differences in a DBT. John Atkinson agrees. jj agreed with that. E-stat agrees.
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"A fool and his money are soon parted." --- Thomas Tusser
training will increase the ability of a person to detect differences in a DBT
And, the more transparent system you use, the deeper into the recording you will hear and differences among components will be more readily observed. Just like any other activity:
It wasn't until I became a more accomplished ice skater and got Reidell Comp 925 boots that I could discern differences between John Wilson vs. MK blades. The MK Phantom provided better support taking off and landing jumps. Riding deep edges was a snap. I no longer had trouble with Camel spins.
It wasn't until I got a Honda S2000 capable of neutral 0.9G cornering that I could readily tell the difference between a truly high performance tire like the OEM Bridgestone S02s and lesser tires with which I experimented. The S02s (also supplied to various Ferrari and Porsche models) offered higher levels of adhesion and better road feel.
It wasn't until I had the chance to shoot a neighbor's highly modified rifle (comp trigger, floating target barrel, etc.) that I appreciated that the particular bullet and loading greatly affected long range (400-600 yd) accuracy.
The examples you give show an improvement in performance, in you skating, in your driving, in your ability to hit the target.
Now, a change in equipment may increase your enjoyment temporarily or long term.
A DBT may determine whether you actually can detect a difference in the sound of your system due to the change in the equipment.
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"A fool and his money are soon parted." --- Thomas Tusser
"A DBT may determine whether you actually can detect a difference in the sound of your system due to the change in the equipment."
Category Error. Tests produce data. Well conducted tests produce evidence. Neither determines anything. People make determinations.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
> ...training will increase the ability of a person to detect differences in a DBT.>
That proves it is a test of the listener's critical listening/test taking skills and invalidates it a scientific test of audio component differences.
In real scientific DBTs, does training the subject change the result of new drug clinical trials?
Laughable.
"That proves it is a test of the listener's critical listening/test taking skills and invalidates it a scientific test of audio component differences."
Well, well, now, I see the source of the confusion. Whoever said that an audio DBT was a test of audio component differences?
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"A fool and his money are soon parted." --- Thomas Tusser
That would be you fewer than thirty minutes after asking that question!
A DBT may determine whether you actually can detect a difference in the sound of your system due to the change in the equipment.
Reading comprehension is not your strongest point. Let's look again at what I wrote.
"A DBT may determine whether you actually can detect a difference in the sound of your system due to the change in the equipment."
Where does it say the test is of the differences in equipment? It doesn't. We already know there is a difference in the equipment, and one need not even turn it on to know that. With reasonably accurate measuring equipment, one could doubt measure the performance of each piece and compare the differences.
As Tony Lauck has pointed out, a DBT provides data, and people determine whether the person doing the DBT can detect a difference from the sound alone. Saying that a DBT does it is a linguistic short cut.
The issue is whether the person doing the DBT can detect the difference from the sound alone.
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"A fool and his money are soon parted." --- Thomas Tusser
Read again the second and third sentences. Aloud, if necessary.
In particular, pay attention to words found in both sentences!
'Differences' and 'differences one can detect from the sound alone' are not the same thing. As I said, reading comprehension is not your strong point. Neither is good will, I would guess.
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"A fool and his money are soon parted." --- Thomas Tusser
After listening to it again, my original feeling remains unchanged... which is that the mindset of those who have heard it remains as unchanged as mine. I think both sides chose the "winner" that corresponds to their POV.
But thanks for posting anyway - it was interesting to hear that again.
.
Scroll down to the post #15 at the link below. There's even a picture to go with it!
Absolutely! I'm sure he remains the Voodoo comic. If only he weren't an A-ho, then he wouldn't have gotten banned here, at Alcoholics and elsewhere.I've mentioned elsewhere that Ammar Jadusingh's posts have had a reverse effect than he intended. The "Audiophile Repellent" post and test backfired on him big time. There's always room for tinkerers who think Harmon-Kardon receivers provide SOTA amplifier performance. :)
edit: Oops, forgot to link to his speaker site: Voodoo Speakers
Edits: 12/12/14
He's a loudspeaker manufacturer now.
That would be a real kicker.
Frankly, I'd be much more comfortable with him being gas station attendant in my home state of New Jersey. Sorry if this notion is not clear, but it's definitely not intended to be racist - just a reference to a very common occupation people of Sikh ancestry hold in NJ.
nt
What a thread!
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
It's also a gift, that just keeps on giving.
Duh! Whoever said one person's DBT results apply to another person? You are arguing with a Straw Man.
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"A fool and his money are soon parted." --- Thomas Tusser
Both directly and indirectly, agreeing with someone else who has said/written exactly that.
Do you need help with search function in this forum?
Really? Evidence please.
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"A fool and his money are soon parted." --- Thomas Tusser
And being Teflon is even worse?As I said - use search function for your own posts, using keyword "DBT". I'd hazard to guess that at least 90% of them imply - directly or indirectly - the lack of "evidence", presented by those who report audible differences. As soon as you ask yourself simple question - "Evidence presented to WHOM?" - your pseudo-confusion should be all resolved.
Edits: 12/04/14
The only thing that's been bad for my health has been sleep deprivation (e.g. last night) from reading absurdly long threads you've linked to. :-)
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Plenty of people of the Objectivist ilk, take unsuccessful (null) double blind test results and generalize from these that nobody can hear differences and in some cases, go further to state that the people saying that they hear these differences are delusional. On those occasions where double blind tests come up with solid statistical evidence that a listener heard something, many of these same people go on to deny the validity of the tests. This shows that these people were never objective in the first place, and certainly not scientists.
I suggest that people who care about such things read the linked thread (and the threads linked off of it).
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
Thanks for posting the thread.
Snippet: "Also note the speed with which I was able to identify the right tracks. On the average it was just 10 seconds which included listening to both "X" and "Y" tracks, voting, and the telling foobar to go to the next comparison. To do that requires remembering exactly what the difference is and having no need to listen to A or B reference samples again."
This quote appears to destroy the old, lame excuse that being **forced** to make **quick** decisions is an inherent flaw of DBT. That requirement doesn’t appear to have hindered the author of the thread. Such a test might be useful insofar as separating gifted/trained listeners from poseurs.
You should understand that the author of the post you quoted is an expert listener. He started out as unable to hear minor differences in blind tests and through years of practice mastered the necessary skills. For starters he knew what kind of artifacts would be likely and how to recognize them when they occurred. You will find this explained in the very long and acrimonious thread linked below.
I would also point out that he was given as much time as he needed. Often he spent a lot of time at first searching for a solid "tell" and characterizing it. Once you've done this then you need to remember only a small amount of information, hence the rapid decision making.
Tony Lauck
"Diversity is the law of nature; no two entities in this universe are uniform." - P.R. Sarkar
navman
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