Meyer & Moran Updated: Proof that CD audio isn't transparent!

However, 6 & 8kHz squares are quite distinctly audible, and their first harmonics are at 18 & 24kHz, which I can't hear.
If the square wave is slightly distorted there will be even harmonics and you will hear a difference. So you were probably hearing the second harmonic of 6 & 8kHz i.e. 12 and 16kHz.
 
Wow that must be a very old article. Right at the end there are adverts for S-VHS leads!

However, he concedes that dynamic range for an LP is around 75dB and suggests that you can hear 10-30dB further below the 'thermal' noise floor thus giving a quasi dynamic range of ~100dB (ignoring any pops and crackle).

He correctly states that digital quantisation destroys any info below that floor. However, what he does not touch upon is dithering which can push the dynamic range in the most sensitive audio bands to 120dB (without any pops and crackles!!!).

Then there is distortion, wow & flutter, rumble, uneven frequency response etc. that he conveniently ignores :).
 
Boy, is it droll reading such bunk at this late date.

I wonder if the Pras Guastavino paper got published in the AESJ, like ours. Oops. I wonder if the citers here actually read it through. I wonder also if Amir has published papers showing his astounding 100% (or any other) acuity. Can't find them. He has gone on to do important audio work.

As Brad and I keep reminding everyone, quoting a statistician and former AES executive and editor, “Given that your test was designed to allow participants every opportunity to demonstrate their ability to discriminate between A and B, you were more concerned that you not get a false positive conclusion than that there not be a possibility of reaching a false negative conclusion.” We reported the results, that's all, of some 60-70 serious audiophiles and adolescents doing blind comparative listening at their leisure to material they often were familiar with.

The line about listeners not having been trained in what to listen for made me literally lol. Now, there's a selling point for hi-rez !

Some background for the record from a followup AESJ letter response:

Our list of sources, and further descriptions of our methods, have been available since late 2007 at BAS Experiment Explanation page - Oct 2007). None of our test discs were reissues of old or inferior material; all were recorded with modern microphones and electronics. Many claims of the superiority of high-resolution audio tout its audibly improved performance even with reissues of old analog recordings. Nevertheless, to address this question we added up all the trials where the original sources were very recent recordings touted as being of demonstration quality from their labels (Chesky, Telarc, ECM, Turtle and Kimber Kable). The average correct score for this group was 45.4% (109/240), slightly lower than our overall average. There were no scores above the 95% confidence level for any listener.

We also collected the results of everyone whose hearing, according to our informal test, extended out to at least 15 kHz. These results totaled 94/212, or 44% correct. This group comprised two subgroups. One was recording engineering students who took the test all together with Meyer switching; their results were 44/104 (42% correct). The second subgroup all took the test in Meyer’s ultraquiet listening room (see Fig. 2 in original report), almost all of them listening alone. This group’s results were 50/108 (46%). No one in the second group made fewer than six attempts and no individual got more than 80% correct. We also looked at all individuals who took the test in Meyer’s listening room, focusing on their first six trials, and then on their last six trials. The former total was 58/16 (46% correct) and the latter was 67/126 (53%). Again, no one in either sample got more than five out of six correct.

As has been noted, there are problems with combining these numbers and it is not clear how much the totals mean. ... [It] is correct that our experiment failed to show with statistical certainty ... that the differences we were testing for were inaudible. (As we have said, we did not design the experiment to do this, nor did we claim it does so.) The probability of a type II error in our results
is too high for us to be able to state with authority that no difference can be heard. If there were subtle differences between the sources that had (to pick a commonly used threshold) a 75% chance of being audible, we might have missed this effect in our analysis of the data. To bring the
probability of a type II error down to 20%, assuming the same 75% audibility, would have required that each subject do 23 trials. Given the length of time each subject was given to make repeated comparisons, and the subjective difficulty of trying to decide whether X was A or B, this would have been impractical, not to say cruel.

We repeat that this test was conceived and carried out as an exploration of differences were / are supposed to be obvious.
 
Boy, is it droll reading such bunk at this late date.

What is the point digging up this old thread now ?
CD and its 16bit 44.1khz rate is as good as dead.

Music shops ( the few that are left ) are wall to wall Vinyl now.
The two biggest streaming services ( the only ones likely to survive ) are Apple and Amazon and they supply ( if you believe them ) copies of the master at whatever rate they exist in.

High spec dacs are cheap as chips.
Vast amounts of storage in the form of massive hard drives are cheap too.
Most are streaming .... there is no reason for the technical limitations of CDs to exist anymore.
Optical Players of all kinds will be gone soon enough. ( the technical cliff edge that is a point of no return is fast approaching if its not already here ... )

Technology marches on , whether you want it or not , "high res" is generally available at no extra cost , so why not ?
High Res in quotes , because I prefer the term "Unadulterated Master" , its closer to the truth.

There is no need to butcher the master to fit saleable formats anymore.
 
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> the technical limitations of CDs
> "Unadulterated Master"
> butcher the master to fit saleable formats

thanks, this is great patter, and I am glad to see it still exists and will almost certainly never go away
 

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