24/192 Music Downloads ...and why they make no sense

[morris_minor]

Apologies if folk have seen this already:

http://people.xiph.org/~xiphmont/demo/neil-young.html

The guy writing is behind the Vorbis format, apparently, so should know a thing or two . .

My technical ability to pick this apart is totally lacking, but on the surface it exposes quite a few myths . . . .

[Bonky]

Apologies if folk have seen this already:

http://people.xiph.org/~xiphmont/demo/neil-young.html

The guy writing is behind the Vorbis format, apparently, so should know a thing or two . .

My technical ability to pick this apart is totally lacking, but on the surface it exposes quite a few myths . . . .

Hi Bob,

No, I can't follow most of it either!

However, you must be a brave chap posting this link in AoS as there is a large following of pure subjectionalists who hate objective testing. Their argument (and I appreciate and even follow their point of view) is that, first and foremost 'trust your ears'. (If you think you can hear a difference then you can).
I once wrote about the importance of the placebo effect and, to a few, this was like a red rag to a bull; they believe that they have the mental apparatus that can overcome this. (Fore-warned is fore-armed I suppose). I have no wish to resurrect the old subjective v objective discussions that were held at great length a short time ago. (This was very good-natured on the whole and generated lots of interesting view-points). However, it has always surprised me how few double-blind A-B trials there are in this field.
Me? I'll trust my ears first, but will, I hope, always be mindful of the importance of theory and objective testing as well.

Let's hope that some of our more technical minded boffins on AoS will be able to help us criticise this link/document.

Thank you for such an interesting link..

Yours,

Bonky

[ursus262]

I read this article with some interest, because I can't, for example, tell the difference between CD and SACD, and I have the ability to play both.

[zygote23]

Excellent article though some of it is tough going (ie over my head).

I've a few hi res downloads and really can't hear a difference. I do treat with the highest suspicion the 'amazing next greatest way of playing your music' as proffered by the odd dealer.

I did go to hear a prototype player that would hold a few thousand tracks, rip your cd's and play hi res tracks as well. It was crap, expensive and the player itself couldn't tell us which tracks were mp3 and which were hi res. It was to cost thousands and when I suggested that a squeezebox would be all you need I was practically laughed at.

Fools and their money will always be easily parted in the hi fi world.

Anyone got a Lexicon.....oops I mean Oppo disc spinner I can have ;)

[morris_minor]

However, you must be a brave chap posting this link in AoS as there is a large following of pure subjectionalists who hate objective testing. Their argument (and I appreciate and even follow their point of view) is that, first and foremost 'trust your ears'. (If you think you can hear a difference then you can).

Well, it wasn't my intention to re-ignite any wars! I just thought it an interesting read, worth commenting on.

Yes - listening yourself (rather than reading about the listening of others!) is the proper way to go whatever the measurement says, because hi-fi exists to play music, not to just be measured on test equipment.

I've a few Classic Records HDAD discs - 96/24 on one side 192/24 on the other. I'll be blowed if I can really hear a difference between the two, but my "feeling" is the 192 sounds better because it "should" :lol:. Or maybe it shouldn't if you believe the article . .

I think a lot of audio manufacturers trade on the insecurity of "audiophiles" who by nature are always trying to "improve" their systems. With the law of diminishing returns, such improvements get smaller and smaller, and may be different but not necessarily better. If you've just shelled out £x on the latest greatest piece of kit everyone else is raving about, the temptation to like it whatever it actually sounds like - and whether or not you can perceive any difference from your old kit - is actually quite strong. And even if you do acknowledge dissatisfaction, another temptation - changing other bits of kit (cables for instance), also rears its head.

Hi-fi is fraught with gotchas at every stage, and maybe, just maybe, the high resolution playback scenario is another one.

[morris_minor]

Anyone got a Lexicon.....oops I mean Oppo disc spinner I can have ;)

:lol:

[Macca]

I've heard SACD on several sytems including my own and it was better than the standard CD on most of them but not all - including mine, but that was with different SACD players in each case (Pioneer, Sony, Oppo). One argument is that the mastering for the SACD release is better than the original hence the pervceived SQ improvement - which sounds plausible. However the Rolling Stones SACD releases are on dual layer discs witrh a re-mastered CD version as well. These should be indistinguishable if hi-rez makes no difference and IMO they are different and SACD layer sounds better on some SACD players/systems.

[bobbasrah]

Read much of this before, and it all makes sense from a technical perspective.
Whatever the arguments are for some as yet unmeasurable effect making a difference, those I have noted throw more questions on what the software/OS/DAC kits is doing differently than the sample as such. How the digital version is mastered is more critical I suspect.
The recent thread on DSOM v Adele threw up one such example where the LP of Adele's 21 is a better playback than the CD. It should not happen, but unfortunately it does, but it will be interesting to compare the CD I have to the rip of the LP when it lands up.

I suspect the key to Apple's success in the 24bit expansion of their iTunes business will depend more on remastering rather than the format. However, when you have successfully built a massive download empire off the back of "CD quality downloads" they could hardly advertise the new downloads as Less Screwed up CD quality..... 24/48 sounds new, and an opportunity to re-sell the old product yet again....

[Macca]

Copmparing a vinyl copy to a digital copy is always going to be an apples and oranges thing for me, even if they are taken form the same digital master. Still it will be interesting to hear what you think of the comparison, Bob.

[sq225917]

He doesn't actually say 'dick' in that article other than reiterate the old 'you can't hear above 20khz' line. He makes no comment about the out of band response of dac chips and their digital filters where accepted increases in quality and a reduction in audible fold-back have been shown to occur many times.

If all he wants to say is that Apple will be pointlessly ripping people off for new material that will sound just as good as standard bitrate when using a quality up-sampler and dac, then he should have said just that. But he shouldn't discount the accepted and proven benefits of performing your filtering on higher bit rate source material.

[PaulStewart]

Yes this is an interesting article from a technical point of view and I thank Bob for pointing me in that direction but I have to agree with Simon that he, "doesn't actually say 'dick' in that article, other than reiterate the old 'you can't hear above 20 kHz' line". *In the late 70s/early 80s, when we were looking at the beginnings of digital domestic reproduction, I was involved in a series of experiments to research the desired upper and lower frequency limits of any such reproduction system. *The manufacturer I was working for, already had amplifiers that, theoretically worked from DC up to well over 100k, so I took advantage of that technology. *

As an aside, and partially relevant to something in the article, the upper frequency response did produce a problem for one customer who kept blowing tweeters with one of our top end wide band amps because he lived near Heathrow and in a certain configuration, his set up would pick the landing radar and the HF pulses would be amplified enough to blow the tweeters. *We also had a more common problem with one of our budget amps, which if plugged into a ring main system, picked up Radio Moscow when it came on air on short wave, causing the amps to cook themselves. *

But to get back to the matter in hand, following on from some finding in the HiFi press by Graham Holliman, we conducted some research, which involved 2 groups of 50 people in the Rainbow Theatre in London in a double blind testing, where we had a reproduction system that would go from 10Hz to 32kHz and the ability to switch the extremes above 20k and below 20Hz in and out. *The listeners were played a series of analogue recordings, recorded on half inch stereo masters, that had been recorded at 30 inches per second and some tracks that had been mastered on an early digital system that utilised high band U-Matic tapes. *The digital systems were brick wall filtered in the 20 Hz - 20 kHz that became the norm for CD and the listeners were asked to mark on a card, which they "preferred", which gave them the most sense of "realism and location" of sounds and which they preferred from a point of view of "tonality". *The combination which came out on top in 87% of the respondents, was the analogue with the full band width. *Further experimentation proved, and I am not going to give all the details here - it was a 26 page document - that it was precisely the brain's ability to detect but not hear the sounds below 20 Hz, which very much aided the perception of "reality" to the reproduction, with the whole of the basilar membrane being vibrated by pressure waves which were passing through the body by these lower frequencies, so there is a physical effect on the body. *Also, with the second group, we tried cutting out the HF but leaving the LF and this did not get as good results as the full band width. *We concluded that, in much the same way as a bat picks up reflections and inter-modulations of sound to localise objects, the brain detects inter-modulations between the higher non audible frequencies those in the audible band and this is what helps ear/brain to localise and position objects, so it is really not all about hearing. *It is about band width, both in the recording and reproduction systems. *

[Welder]

A link to the study and results would be handy Paul.

[PaulStewart]

Hi Welder,
This study was concluded in 79/80 and was commercially sensitive at the time and of course well before the www. I have asked for it to be posted, or permmission to post it many times, to no avail. Spured on by this new debate I will try again.

[Welder]

That would be cool Paul.
Naturally enough when someone posts citing the results from a test/survey/trial particulary one that involves such a large group and in such a interesting location one wants to view the test conditions and results. ;)

[morris_minor]

Thanks for the details on the study Paul. It makes interesting reading. I've always thought that "inaudible" higher frequencies in musical tones emanating from the upper harmonics of notes were "perceived" by listeners if not exactly heard. Any brickwall filtering would naturally eliminate these, which is why CD playback has often come a poor relation to analogue playback for many people.

[ursus262]

If you play a 30 kHz tone or a 31kHz tone, you will hear neither. Play both together, and you do hear something.

SACDs do capture these ultrasonic tones and, although we cannot hear them, they interact with each other, producing the timbre of instruments and the environment in which they are being played.

That said, I still cannot hear the difference between SACDs and CDs. I have one SACD that has the same master for both layers (CD and SACD layers), and I'll be buggered if I can tell the difference.

[Welder]

Bob, it seems you’ve assumed that it is possible to not only record a greater frequency range onto vinyl than it is on CD, but also retrieve that information.
You’ve also assumed that brick wall filtering is confined to the production of digital sound.

I’m fairly open minded regarding the possible benefit of greater bit depth and higher frequency recordings despite not being able to differentiate between otherwise identical recordings at 24/96 and 24/192.

[morris_minor]

I have one SACD that has the same master for both layers (CD and SACD layers), and I'll be buggered if I can tell the difference.
I'm sure the Emperor's New Clothes syndrome is endemic to hi-fi. It's so much easier to follow the majority than stick your own neck out and say "actually - that's rubbish".

But if something sounds better for you, then it's better. The problems come when you try and convince others to hear the same as you. Everyone's brain is different, and therefore our perceptions are different - not to mention learned preferences and an individual's peer-pressure.

[ursus262]

I'm sure the Emperor's New Clothes syndrome is endemic to hi-fi. It's so much easier to follow the majority than stick your own neck out and say "actually - that's rubbish".

But if something sounds better for you, then it's better. The problems come when you try and convince others to hear the same as you. Everyone's brain is different, and therefore our perceptions are different - not to mention learned preferences and an individual's peer-pressure.

I absolutely and wholeheartedly agree.

I'm sick of this polarised debate between the objective and the subjective. It's circular and goes nowhere. Every piece of hi-fi equipment we own is an engineered component taking into account the laws of physics from which engineering principles are derived. The bits that really makes the difference, are the acoustics of the listening room and the perceptions of the listener - psychoacoustics. These are the variables that can't be measured because we, as human beings, are immensely complex and it's impossible to account for all these variables.

Also, a neutral-sounding system, is a system that presents the listener with an absolute facsimile of what was present in the concert hall when the recording was made. That is what hi-fi is all about, surely! Anything else that gives us the sound we actually want is coloration - nothing more and nothing less, and it is here that the subjective comes into play. Much about what is discussed on this forum is not about hi-fi at all, it's about finding a combination of kit that entertains us, which is something different entirely.

[zygote23]

I absolutely and wholeheartedly agree.

I'm sick of this polarised debate between the objective and the subjective. It's circular and goes nowhere. Every piece of hi-fi equipment we own is an engineered component taking into account the laws of physics from which engineering principles are derived. The bits that really makes the difference, are the acoustics of the listening room and the perceptions of the listener - psychoacoustics. These are the variables that can't be measured because we, as human beings, are immensely complex and it's impossible to account for all these variables.

Also, a neutral-sounding system, is a system that presents the listener with an absolute facsimile of what was present in the concert hall when the recording was made. That is what hi-fi is all about, surely! Anything else that gives us the sound we actually want is coloration - nothing more and nothing less, and it is here that the subjective comes into play. Much about what is discussed on this forum is not about hi-fi at all, it's about finding a combination of kit that entertains us, which is something different entirely.


Well said that man.

I have settled myself to listening to music rather than gear! FYI I am sitting upstairs working whilst listening to Tord Gustavsen streaming downstairs in the kitchen. He has to try really hard as the sound has to travel right upstairs and into the loft where I am. Heaven knows why I don't just play it through the pc here or even stream to the squeezebox boom in the room behind me! Anyway it sounds grand and hasn't cost me a fortune so I am happy ;)

[morris_minor]

Well said that man.

I have settled myself to listening to music rather than gear! FYI I am sitting upstairs working whilst listening to Tord Gustavsen streaming downstairs in the kitchen. He has to try really hard as the sound has to travel right upstairs and into the loft where I am. Heaven knows why I don't just play it through the pc here or even stream to the squeezebox boom in the room behind me! Anyway it sounds grand and hasn't cost me a fortune so I am happy ;)

Oh yes! Music rather than gear! And Tord Gustavson too :). A firm favourite of mine also . . .

[morris_minor]

Bob, it seems you’ve assumed that it is possible to not only record a greater frequency range onto vinyl than it is on CD, but also retrieve that information.
You’ve also assumed that brick wall filtering is confined to the production of digital sound.

I’m fairly open minded regarding the possible benefit of greater bit depth and higher frequency recordings despite not being able to differentiate between otherwise identical recordings at 24/96 and 24/192.

I was very careful, John, not to mention vinyl! (I have no wish to start up that debate again . . :rolleyes:). But, since you mention it . . . during the great Quadraphonic fiasco of the 70s and 80s, JVCs CD-4 system used a frequency modulated carrier signal of around 35KHz to separate front from back channels. To retrieve this information they developed the Shibata stylus profile so it accurately tracked this carrier frequency. In my mind, then, very high frequencies can be had from vinyl. Whether they are present in the first place is another matter, and something that I have no opinion on.

The author of the article was careful not to dismiss higher bit rates - it was the higher sampling frequencies that he questioned. Personally, I choose 96/24 downloads when there's a choice. I rip LPs in 96/24 but often store the edited files at 48/24 - I really can't hear a difference. Just as I said the 96/24 - 192/24 comparison left me guessing which was which. Common sense seems to tell you that higher everything should be "better". But if you can't actually hear the difference on playback what does it matter? Why bother getting that new DAC for 192 playback? Unless it's like having a car that do 200mph. You never, ever, use it at that speed, but it's nice knowing you could . . ;)

[dave2010]

If you play a 30 kHz tone or a 31kHz tone, you will hear neither. Play both together, and you do hear something.

SACDs do capture these ultrasonic tones and, although we cannot hear them, they interact with each other, producing the timbre of instruments and the environment in which they are being played.

[**]That said, I still cannot hear the difference between SACDs and CDs. I have one SACD that has the same master for both layers (CD and SACD layers), and I'll be buggered if I can tell the difference.
I have had similar experiences. Telling the difference beteen 2 channel SACD and CDs can be very hard or even impossible. Certainly at an individual level I think it's hard to be sure. I'm not sure if there have been any scientifically conducted tests which do show that some people do have the ability to discriminate consistently between them.

My own hearing varies. Some days I can hear my watch ticking (loudly) and sometimes not. I can usually do this with my left ear, less frequently with my right. Anti-histamine medication for hay fever or other medication can sometimes have quite a big effect on my hearing, I think because it reduces swelling in the tubes round my ears, and allows them to drain. I'm not recommending medication as yet another hi-fi tweak though! Others may extend that idea to drug taking etc., which I suspect is a really bad idea.

Having said that, I think there is a slight difference, with SACDs generally sounding smoother, but that could of course be due to mastering and different quality playback systems.

"Hi-Fi" is often accompanied by snake oil and emperor's new clothes phenomena, but that doesn't mean that every "improvement" is worthless. I can tell the difference between wax cylinder recordings and recordings made in the last three or four decades, either analogue or digital.