Did he name the sampling rate convertor?  If so, if in its owner's manual it mentions, say: "Be advised the optional use of rectangular dither [RPDF or "Rectangular Probability Density Function,"] instead of TPDF, may cause audible noise modulation", then he's dead meat.

How about absolute SPL used for the tests? Source songs? Source machine?

It's a convention paper -- so, not even peer reviewed.  (It's also a completely in-house affair -- all three authors work for Meridian).

Thus, I expect Our Man from  Madrona will reject it forcefully, using at least three if not four different font colors.

Why DVD-A, SACD? Good question. There is no good evidence that they sound different to people over the age of 10 or so.

Did he give an explanation why rectangular dither was used instead of triangular, considering it is know to introduce noise modulation which triangular is immune from?

^The abstract (summary) at the beginning of the paper should tell you everything you need to know. If some aspect of it is unclear to you, ask.

http://www.aes.org/e-lib/browse.cfm?elib=14195

In the "old" paper 0 dBFS is referenced to 120 dB spl when audibility of (dither) noise is calculated. This seems very loud to me, especially with modern loudness-war pop music. Is this spl reference still used in the new paper ? (which I refuse to buy, pretending I'm not an audio forum addict)

There is a more general problem with listening tests
of this kind, which concerns the testing procedure.
ABX tests are viewed as the "gold standard" for
objective measures of listening. In an ABX test, a
listener is required to listen to two reference sounds,
sound A and sound B, and then to listen to sound
X, and to decide whether sound X is the same as
sound A or sound B. ABX tests have a high sensi-
tivity, that is, the proportion of true-positive results
out of total positive results is high. However, ABX
tests also have low specificity, meaning that the pro-
portion of true-negative results out of total negative
results can be spuriously low. Translating this into
outcomes in psychophysical tests, the proportion of
the time that a listener scores well on an ABX test
by chance is low, but the proportion of the time that
a listener can score poorly on a test in spite of being
able to discriminate the sounds is high. An ABX
test requires that a listener retains all three sounds
in working memory, and that they perform a min-
imum of two pair-wise comparisons (A with X and
B with X), after which the correct response must be
given; this results in the cognitive load for an ABX
test being high.

It's amusing how *fragile* this perception of difference between hi rez and CD is....it can barely withstand ABX testing.  Here's Stuart's* new iteration of the anti-ABX stace, from the Introduction section of his new Convention paper

ABX tests are viewed as the "gold standard" for objective measures of listening.

the proportion of the time that a listener can score poorly on a test in spite of being able to discriminate the sounds is high.

An ABX test requires that a listener retains all three sounds in working memory,

and that they perform a min- imum of two pair-wise comparisons (A with X and B with X), after which the correct response must be given; this results in the cognitive load* for an ABX test being high.

The aspect of memory on testing has been discussed to death, AFAIC, with the outcome of such discussions never seeming to benefit the anti-DBT crowd.

However, why are people who are not even present in the discussion being debated here?

However, why are people who are not even present in the discussion being debated here?

Wonder if jj knows his old boss finally has that long missing whit of evidence, now being touted on several forums?

cheers,

AJ

I came here to see what HA's take is on Stuart's latest work and most of what I read is about me???  Is the technical topic not interesting enough by itself?

Why DVD-A, SACD? Good question. There is no good evidence that they sound different to people over the age of 10 or so

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

P.S. I typically ignore that troll in that other forum but anyone wishing to use any of this, by all means do so, and no need to reference me. [Also keep in mind he's quite likely reading all of this.]



Here are some guidelines to follow:

Ten (10) Requirements For Sensitive and Reliable Listening Tests

(1) Program material must include critical passages that enable audible differences to be most easily heard.

(2) Listeners must be sensitized to a audible differences, so that if an audible difference is generated by the equipment, the listener will notice it and have a useful reaction to it.

(3) Listeners must be trained to listen systematically so that audible problems are heard.

(4) Procedures should be "open" to detecting problems that aren't necessarily technically well-understood or even expected, at this time. A classic problem with measurements and some listening tests is that each one focuses on one or only a few problems, allowing others to escape notice.

(5) We must have confidence that the Unit Under Test (UUT) is representative of the kind of equipment it represents. In other words the UUT must not be broken, it must not be appreciably modified in some secret way, and must not be the wrong make or model, among other things.

(6) A suitable listening environment must be provided. It can't be too dull, too bright, too noisy, too reverberant, or too harsh. The speakers and other components have to be sufficiently free from distortion, the room must be noise-free, etc..

(7) Listeners need to be in a good mood for listening, in good physical condition (no blocked-up ears!), and be well-trained for hearing deficiencies in the reproduced sound.

( Sample volume levels need to be matched to each other or else the listeners will perceive differences that are simply due to volume differences.

(9) Non-audible influences need to be controlled so that the listener reaches his conclusions due to "Just listening".

(10) Listeners should control as many of the aspects of the listening test as possible. Self-controlled tests usually facilitate this. Most importantly, they should be able to switch among the alternatives at times of their choosing. The switchover should be as instantaneous and non-disruptive as possible.

Hey AJ.  How the heck have you been kid?  I see in your signature says you still trying to sell speakers?  I can't think of a worse business than selling audio equipment.  Was hoping by now you would have seen the merits of that.

As to JJ, I honestly don't understand the constant name dropping there. That somehow you know his position in audio better than me?  I don't think so .

But yes, this latest evidence from Stuart is quite strong.  It is the first professional test of this type vs hobby work that Moran and Meyer performed.  And the paper shows it.  It is far more than "whit of evidence."  If you were pushing Meyer and Moran around in forums, I suggest pulling back some or you will have your hat handed to you.  In other words, stop being yourself AJ.

Welcome amir! 

Yes, that was intentionally done. I of course knew you were reading/lurking, so I figured I could (would) eventually flush you out. 
Forgive my methods, despite the effectiveness.

Regarding your recent success with the corrupt/gameable/non-proctored online amateur AVS files and now the Stuart paper, have you enlightened jj with these 2014 revelations, given his 2009 and 2012 positions on the subject?

Quote from: Woodinville on 2012-08-14 00:07:23

Why DVD-A, SACD? Good question. There is no good evidence that they sound different to people over the age of 10 or so

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

Based solely on credentials, I'm leaning towards jj and away from Stuart, who has pecuniary interests in the matter. Do you disagree?

You also said the Stuart paper was "available for free on the Meridian website". Link?

First, if the test is corrupt, let's see the results of you passing it AJ.

First, if the test is corrupt, let's see the results of you passing it AJ.  You can use the cheats but however you do it, let's see the output of foobar.  If you cannot pass it, then we have proven a very significant thing: that our abilities to listen differ.

"It should be understood that the topics of experimental design, experimental execution, and statistical analysis are complex, and that only the most general guidelines can be given in a Recommendation such as this. It is recommended that professionals with expertise in experimental design and statistics should be consulted or brought in at the beginning of the planning for the listening test."

Well, by that logic I have better credentials than you in this area but you are not going to take that as an argument, are you?

Stuart is one of the luminaries of our industry.

He is an AES fellow and one of the few people who has both knowledge of audio engineering/science, especially signal processing, and psychoacoustics.  That he is a founder of Meridian did not bring down his position in AES and should not do differently here.