What's the use of a 192 kHz sample rate?
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From: Jerry Avins on 4 May 2008 10:50 rajesh wrote: > On May 3, 5:42 pm, Piergiorgio Sartor > <piergiorgio.sartor.this.should.not.be.u...(a)nexgo.REMOVETHIS.de> > wrote: >> Randy Yates wrote: >>> The curve on p.20 of >>> http://www.dohc.ie/publications/pdf/hearing.pdf?direct=1 >>> indicates that, even for young adults, sound at <20 kHz is >>> inaudible. Based on this, a 44.1 kHz sample rate should be ample. >> The problem might be that a "sound" is not only >> perceived with ears, but with the full body. >> >> One specific issue are the sudden transitions of >> pitches that real world instruments can create, >> and, possibly, are picked up by different means. >> For example, the sound waves going through the >> skull, brain tissue and then to ears (from inside) >> are "distorted" and, maybe, remodulated, so that >> a person *could* receive "signals" (from real >> instruments), which otherwise would be wiped out >> by sampling low-pass filter, in case of 44.1KHz >> sampling rate. >> >> That's the theory. >> Is this true? I don't know, maybe, maybe not. >> There are people swearing this is the case, others >> say that's nonsense. >> There are people citing Dolby technologies taking >> into account these alternate perception paths, but >> I could not find any real reference. >> >> Nevertheless, one thing is sure (and proven) sound >> waves are not only "eared", they're generally >> perceived by the full body, but the studies I know >> always refer to bass and not to ultrasounds. >> >> bye, >> >> -- >> >> piergiorgio > > I agree that humans cant hear above 20k rate > > Its not always about what you hear or percieve with your body. > > Its also about how you store data. > > here is an simplified analogy. > > say you need 44.1k samples per second to hear properly. If the disk > is corrupted with scrathes > and 1 samples in his region are lost your sound is distorted or > lost for that period of time. > Now if there are 196k samples even if (196/44.1) samples are lost > there is no difference to what you > hear. > > DVD's come wih high density of data due to this they are highly > vulnerable to scratches this can be avoided > with better waveform matching achieved by high sampling rate. Oh come now! How often do you suppose that one might lose alternate samples? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
From: dpierce.cartchunk.org on 4 May 2008 11:01 On May 3, 10:34 am, rickman <gnu...(a)gmail.com> wrote: > Do you have any "proof" that no one can hear the difference? Wrong question. That's not the way it works. Can I PROVE the mnoon is not made of green cheese, and that NO part of the moon is made of green cheese? Nope, rather the proof is up to those who claim it is. Can I PROVE that NO human can self-levitate? Nope: it's not the job of me or anyone else to prove that YOUR extraordinary claim is false, it's YOUR job, YOUR responsibility, if you want to be taken at all seriously, to prove the extraordinary claim. Do YOU have ant proof that one can hear such differences? No anecdotes, no "I had a dealer friend who ...," rather verifiable, repeatable, credible proof. Given the extraordinary amount of science and engineering that has been spent testing and describing acoustical psychophysics, for someonem, such as yourself, to come along with a claim that, on its face, seems to contradict well over a century of research, seems to constitute an extraordinary claim. Fine, you may be right. But it's not up to the rest of the worl to prove you wrong, it's up to you to provide the proof you're right. That's the way science and technology are SUPPOSED to work. Unfortunately, these pronciples and methods are rather inconvenient for much of the audio world. To f***ing bad.
From: "Ethan Winer" ethanw at ethanwiner dot on 4 May 2008 11:08 Rick, > This seems to indicate that the tests do show the higher formats to be > equivalent to CDs. Yes, which is the main point of the tests. > Maybe I just don't understand this report, but I see sections where they > claim that the blind tests showed 100% correct results??!!! That addresses background noise only, not audio quality. As I read it, they found only one hi-res disc that had a noise level lower than regular CDs. And they had to turn up the playback volume way higher than normal to hear that. > The question is *not* about ultrasonic content. The question is about > recording and playback systems using different sample rates. Actually, the real question is why people sometimes report hearing a change in audio quality when no change is possible. As with tiny magic stick-on plastic dots, replacement AC power cords, cryo treatment, and so forth. That's the core issue underlying ALL of this stuff. Which is what my article addresses. Did you read my article? Most people - even many audio pros - have no idea how pervasive comb filtering is. > You are free to buy any system you want. Why do you care what other > people use? This is an excellent question. People who are already convinced their BS tweaks are worthwhile should buy what they want and I have no objection. But the majority of people are seeking an honest opinion to avoid wasting money. I see this as a consumerist issue, so I aim to educate those who really want to know. --Ethan
From: dpierce.cartchunk.org on 4 May 2008 11:10 On May 3, 9:16 am, rajesh <getrajes...(a)gmail.com> wrote: > Its also about how you store data. > > here is an simplified analogy. Yes, simplified to the point of being factually wrong. > say you need 44.1k samples per second to hear properly. > If the disk is corrupted with scrathes and 1 samples in his > region are lost your sound is distorted or lost for that period > of time. Wrong. First, you have a pretty robust error correction scheme built in to the disk. The encoding and decoding is such that significant amounts of data can be lost but can be EXACTLY reconstructed on playback with NO loss. And if the disk is severely scratched to the point where the error correction algorith fails, interpolation takes place. One can see thousands of uncorrected errors in the raw data coming of the disk, and once the error correction has been applied, the result might be a SMALL handful (like, oh, 4?) uncorrectable but interpolated errors > Now if there are 196k samples even if (196/44.1) > samples are lost there is no difference to what you > hear. False. Since you're cramming more data into the same area, and the physical faults take up the same area regardless of the data density, more bits, according to YOUR theory, will be lost on the higher density disk than on the lower density disk. That means MORE data is missing, that means the error correction algorith is subject to higher rates of non-correctable errors, and so on. Your theory is bogus if for no other reason than it simply ignores the facts. But, in EITHER case, unless the disk is SERIOUSLY damaged, the data loss in either case is repaired. > DVD's come wih high density of data due to this > they are highly vulnerable to scratches this can > be avoided with better waveform matching achieved > by high sampling rate. Sorry, this is nothing but technobabble nonsense.
From: dpierce.cartchunk.org on 4 May 2008 11:11
On May 3, 3:01 pm, vlad <vova.kuznet...(a)gmail.com> wrote: > On May 3, 8:11 am, Vladimir Vassilevsky <antispam_bo...(a)hotmail.com> > wrote: > > > rickman wrote: > > >>Utter nonsense - unless of course you can cite some proper tests. > > > > And what do you base this statement on? > > > The ultimate reason for the audio systems is making the people happy. If > > someone is happy because of 192kHz sample rate, and willing to pay for > > that, then why do you need to proove anything? Heck, if someone orders a > > 192MHz audio system, it would be my pleasure to do this project. > > > Vladimir Vassilevsky > > DSP and Mixed Signal Design Consultanthttp://www.abvolt.com > > I guess, you are in business of separating fool from his money. Welcome to the world of high-end audio. |