Can digital audio playback be improved by resolutions greater than 16/44.1?

You are right to point out that the study finds differences, not improvements. That is the first step. Presumably the next step is to establish why these differences are perceived, and then whether there is a preference for hi-res. It has every bearing on this thread without providing a definitive answer yet.

I think it is unwise to level an accusation of lying based on a PR statement. Journalists and/or University PR Departments routinely misunderstand or misquote scientists. Dr Reiss makes no such statement in his published paper.

WHAT!!?? Dr. Reiss was the one making the PR statement!

The full quote is here:

https://www.sciencedaily.com/releases/2016/06/160627214255.htm

Dr Joshua Reiss from QMUL's Centre for Digital Music in the School of Electronic Engineering and Computer Science said: "Audio purists and industry should welcome these findings -- our study finds high resolution audio has a small but important advantage in its quality of reproduction over standard audio content."

I stand by my accusation. Dr. Reiss is lying in his PR statement. If you think this is "unwise", then the onus is on you to prove the quote is false. Good luck!


As to whether he can prove anything about the superiority of Hi-Res, my question was quite specific, this "study" says nothing towards that question, and is thus irrelevant. I imagine we have a better chance of him actually including studies that find there is no difference, like the M&M study, in his next meta-analysis than we have of him proving there is a preference. That is; slim to none. This study was a carefully crafted shill for the Hi-res audio industry, and even so, it proved nothing. The author had to lie in his PR statement in order to accomplish his goals.

Let me point out, having been "quoted" in a few PR statements myself, that often the quote isn't what the person said, it's what the marketing people want the person to say.

I don't know whether he really said that, or was told to say that.

On the other hand, I'm enjoying this discussion. Thank you all for adding to my knowledge.

This study was a carefully crafted shill for the Hi-res audio industry...
You state this as fact rather than opinion. You need to provide solid evidence or withdraw the remark.

...and even so, it proved nothing.
Another statement of fact for which you will need to provide proof. In this case, it would be appropriate to contest a peer-reviewed paper with a dissenting publication.

I remind you of this statement you made recently:
As stated, opinions are fine. It's once someone starts making definitive claims that they need to start giving proof.

So preface it all with "in my opinion", just as everybody else already inferred. Except the "it proved nothing" statement, which is a clause describing the use of the study as a shill for the Hi-res industry, and it indeed provided no proof of any advantage for Hi-res audio. Your convenient snipping of the context of my posts does not go unnoticed.

Then go ahead and pat yourself on the back for switching the conversation to semantical childishness after you were made to look stupid about the PR quote. Then maybe we can get this coversation away from the kid's sandbox and back to discussing things like adults?

By the way, no comment on the PR quote and what it means with regards to any bias shown in the disclusion of seminal studies on Hi-res audio like the M&M study? Also, explain why studies that did factor in the existence of IM distortion were left out, whereas studies that didn't consider IM were included?

Or are you just going to play gotcha?

So, once again, the meta-analysis results do not state there is an qualitative advantage and thus irrelevant to this thread.

One question to the author, if the quote which stated the opposite was not what you said, why have you not requested a retraction? It's a pretty embarrassing statement, and a poor reflection of one's scholarship. If it were me, I'd be scouring the internet for every reference of that quote and requesting it be changed. Yet I see it in dozens of places touting the benefits of Hi-res music where none definitively exist.

Apologies in advance if I don't respond to many other queries.

why have you not requested a retraction?
Short answer is that I do request corrections when anything I publish contains errors. But I wasn't the author of this, it was just a press release, 'important advantage' sounds to me like opinion rather than a factual claim, I can see how it could be used as a layman's phrasing of 'statistically significant', and scouring the internet would be impossible.


“I have [yet] to come across even one for hi res that does a decent job of doing level matched blind AB, leave alone a full protocol ABX… may I be pointed to even one ABX done in line with well established principle” – see the paper.
I have seen the paper. But is there any way to see a fully documented test itself? A link to one perhaps - that is the only way to it for most of us.
Unless I read the documented test, I can't conclude to how good it is. I may still not be able to do that, but it will be more than anything I have been able to find till now. By good, I mean how well single variable ABX protocols have been complied with.
Thank you in advance.

Most of the studies analysed in the paper were published by the Audio Engineering Society. They are all available from http://www.aes.org/e-lib/ , and can be downloaded freely by AES members.
One non-AES paper that can be downloaded by anyone is at https://www2.ia-engineers.org/iciae/index.php/icisip/icisip2013/paper/viewFile/160/146 . I don't by any means claim that this is the best, and it used an AB style paired comparison rather than ABX, but it should give you an idea of what a lot of the studies were like.

Apologies in advance if I don't respond to many other queries.
Short answer is that I do request corrections when anything I publish contains errors. But I wasn't the author of this, it was just a press release, 'important advantage' sounds to me like opinion rather than a factual claim, I can see how it could be used as a layman's phrasing of 'statistically significant', and scouring the internet would be impossible.


I'm sorry, but this is stretching the bounds of reality. No matter how many semantic arguments you wish to put forth, not even a layman would equate 'statistically significant' with 'important advantage'. I stand by my point; stating this study showed a 'important advantage' isn't justifiable marketing spin, or a translation to layman's terms; it is a flat out lie.

And If I were quoted as such when my results said nothing of the sort (in fact they say quite the opposite), I personally would request a retraction. I don't care it it was presented as an opinion, a fact, or an edict from God. I've seen no retraction, so I am left to think that you agree with the "layman's phrasing" which even to a layman, is a gross misrepresentation of the facts. This is pure marketing BS, and you seem to be a willing participant in that BS.

In short, it is astonishing that you would blame a mere misunderstanding, a marketing speak translation, or a dumbing down for laymen for what is in reality a lie, attributed directly to you. I'm left to wonder if AES's apparent support of all things Hi-Res has any bearing on your agreement with this "layman's phrasing".

It really is necessary to come as close to a 100% elimination of bias to have a dependable result... tester bias cannot be ruled out.
Good point and I fully agree.

I don't see that it is a double blind one.
Another hi-res evaluation paper by some of the same authors stated 'an operator was in a blind area outside the vehicle. It was not a double-blind experiment, but the subject and the operator could not communicate each other.'
I spoke with one of the authors for clarification on other aspects, and they used similar methodologies in both papers. So its likely only single blind, but with significant effort to reduce tester influence.

I haven't been able to get enough clarity on the outcome that approx 57% prefer HR to CD ah, that's the nature of these sorts of perceptual evaluation tests. They are actually well established throughout psychophysics (and applied to things like taste tests, perfume preference testing etc.), but its not your typical experimental and control groups as in evidence-based medicine. Think of the control as what would happen if participants were guessing. Then the outcome would be 50%. Note that a 50% result in a preference test with lots of trials does not necessarily imply that those participants can't discriminate, since it could be, for instance, that everyone can perceive the difference but half the participants prefer A and half preferred B. But a 100% result in those circumstances would be extremely unlikely to occur by chance.

For this experiment, standard error of the mean slightly overlapped 50%, so not considered significant. But it had a small number of participants and trials.

My understanding of human memory of sound quality is that it degrades in seconds and becomes unreliable - yes, and that would weaken any ability to discriminate. On the other hand, there is also the effect of auditory sensory memory. Studies suggest that it actually persists for quite some time. If the higher resolution content is played first, then one might retain the perception of that content if the lower resolution is played after (assuming that there's anything there to be perceived). And since we are looking at the limits of perception, long samples might be needed for listeners to identify differences. I grouped studies into those with short samples / quick changeovers vs long samples / long changeovers and the latter had much stronger results. But I wouldn't read too much into this since other differences between studies might have been the cause of this.


I haven't seen any test that adequately rules out bias and takes into account human auditory issues including memory duration, and proves a preference for HR. Even if people can hear a difference and even if that difference is due to higher quality, I doubt you'll find rigorous and general proof of preference. Such is the nature of subjective testing at the limits of perception and dealing with real world conditions. I'll give a couple of examples. In one study, participants were asked which audio format was best quality, and the live feed was the one most often ranked worst, suggesting that perhaps people didn't associate quality with purity. And a classic 1956 study suggested that those who have grown up listening to low quality reproductions may develop a preference for it.

if as you say a lot of the studies were like this, I am afraid that any meta analysis of these is just as flawed in its conclusions.
This is the big challenge with any meta-analysis, but luckily there is a lot of good advice from meta-analysis experts on how to deal with it. When I first started looking into this, it became clear that potential issues in the studies was a problem. One option would have been to just give up, but then I'd be adding no rigour to a discussion because I felt it wasn't rigourous enough. And its the same as not publishing because you don't get a significant result, only now on a meta scale. So I set some ground rules. I committed to publishing all results, regardless of outcome. I included all possible studies, even if I thought they were problematic (but discuss in detail potential biases). I decided that any choices regarding analysis or transformation of data would be made a priori, regardless of the result of that choice. And I did sensitivity analysis looking at alternative choices (like whether to exclude studies or analyse them differently).
One interesting thing that I found, which I did not at all expect, was that most of the potential biases would introduce false negatives. That is, most of the issues were things like not using high res stimuli, or having a filter in the playback chain that removed all high frequency content, or using test methodologies that made it difficult for people to answer correctly even when they heard differences.

Hi everyone, and @joshr thanks for joining us! This is a great discussion, and I'd just like to remind everyone to respect the rules of the community and withhold from personal attacks or letting the heat of the discussion make you forget that this is a welcoming place where everyone is entitled to their opinion. Let's keep it friendly!

Thanks!

... which made the effect of other factors like duration seem weak at best.

As for 2, you would clearly be comparing something very different if you look at commercial HD and CD quality recordings, if anything else was done in mastering besides just sample rate and bit depth conversion. But this argument works both ways of course. If the HD version is just an upsample of CD quality content, then its highly unlikely that there would be significant perceivable differences. Luckily, almost all studies avoided anything like this, and potential biases were noted and discussed when any such issues could have occurred.

If the HD version is just an upsample of CD quality content, then its highly unlikely that there would be significant perceivable differences. Luckily, almost all studies avoided anything like this, and potential biases were noted and discussed when any such issues could have occurred.
I agree that in the study I was able to read about, this issue isn't a factor; but in the real world HR audio is almost aways sold after remastering the recording used for the original CD. Because - I suggest - this is the only way for it to sound audibly different in the real world of normal homes and listening environments, to make people that already have the original CD, to buy it again. And so that those that do not, buy it at a higher price than the original CD that is still on sale.

I doubt that there is anyone successfully selling HR music closely allied to the kind you refer to - where both the HR and the CD are being sold at different prices, but are recorded at the same levels from the same master, and just down sampled for the CD version.

IMO and to my mind this has been a good discussion that has reinforced for me the philosophy that real world improvement in sound quality can be obtained - if required for the enjoyment of music - only via paying attention to who is doing the mastering and to speaker quality and placement/room acoustics/room response DSP. That is where there are real improvements to be found.

Of course, when the day comes that the good masterings are only available in HR format, it will be a different matter. But as of now there are no trends that indicate that this sorry state of affairs will come to pass!

Unable to navigate to page 3 of this thread. InSided, lol. Maybe this post will fix...

Yes, Hi Rez is much ado about nothing in the lives of the vast majority of us music lovers. Primarily of interest only to those trying to make a buck off of it, which includes a lot of shady companies and the magazines which support their claims without question. Objective journalism has no place in "high end" audio reporting these days, unfortunately.