What's the use of a 192 kHz sample rate?
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From: geoff on 4 May 2008 18:19 rickman wrote: > If it really is a waste of time and money to use 192 kHz ADC and DAC, > why do you think they would do it? Don't you think the people > designing DVD equipment understand the economics of consumer > products? > > Try to think about it and see if you can come up with a couple of > reasons yourself. I'll be interested in hearing what you think. There are 3 reasons why people design and manufacture 192KHz equipment: 1 - They imagine it makes a difference. 2 - The technology is available, so why not 3 - Everybody already has 44k1/48K gear, so what would we sell them otherwise.... geoff
From: Oli Charlesworth on 5 May 2008 06:37 On May 5, 8:47 am, rajesh <getrajes...(a)gmail.com> wrote: > On May 4, 8:10 pm, dpierce.cartchunk....(a)gmail.com wrote: > > > > > 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. > > Thanks ! Your facts are proving my point. > Repeating samples is the most simplest form of error correcting codes. > All your error correcting codes and interpolation techniques become > 196/44.1 folds > more robust on 196 kHz signal compared 44.1 kHz signal. No, they don't. If the same FEC techniques are used on both discs, then for the same proportion of raw errors (read errors), the number of uncorrectable errors will be the same. However, as dpierce already pointed out, given the same physical damage to both discs, the high- density disc will experience a proportionally higher density of raw errors, therefore the number of uncorrected errors will be higher. The same logic applies to interpolation techniques. Your "explanation" could only work if the high-density player was designed to interpolate over errors and then downsample to 44.1. -- Oli
From: Arny Krueger on 4 May 2008 19:06 "rickman" <gnuarm(a)gmail.com> wrote in message news:f5ef0294-41cb-4d9b-a3ca-266e192fe624(a)l42g2000hsc.googlegroups.com > On May 3, 3:35 pm, Oli Charlesworth > <ca...(a)olifilth.co.uk> wrote: >> On May 3, 5:26 pm, dpl...(a)radagast.org (Dave Platt) >> wrote: >> >> >> >>> There may be _some_ justification for it, as it >>> eliminates the need to place the knee of the >>> anti-aliasing filter anywhere near the range of >>> frequencies that one _can_ hear. One of the criticisms >>> made against CD is that the sharp filtering which must >>> be done at around 20 kHz can cause artifacts which may >>> be audible to some listeners, either due to >>> "pre-ringing" (with a symmetric FIR low-lass filter) or >>> a frequency- dependent delay and "smearing" of >>> transients (with an IIR filter). >> >>> These effects can be moved up to higher frequencies, >>> and prevented from having effects in the human hearing >>> passband, by increasing the sampling rate. >> >> Indeed. But this problem is largely solved by >> oversampling at the DAC, without requiring an increased >> sample rate at the storage-medium level. Right, the data that is stored might be for example at 44,100 Hz, but the oversampling process involves temporarily using a sampling rate of for example 5 times that or about 220,500 Hz. > And how exactly do you over sample at the DAC without a > filter? There is still a filter, but its at a frequency related to the oversampling, not the sampling.
From: Arny Krueger on 4 May 2008 19:42 "robert bristow-johnson" <rbj(a)audioimagination.com> wrote in message news:a63a85d4-bb01-43ba-bcd0-7429f7088619(a)w7g2000hsa.googlegroups.com > i have never completely accepted that ABX testing is > better than "same/difference testing" (what i used to call "AB testing") > for the question we are trying to answer here. ABX is based on same/difference testing. ABX facilitates same/difference testing. > ABX is for answering the question: which is better? Not really. It is for answering the question: are they the same or different? > or which is closer? does synthesizer A sound more like a real piano > or does synthesizer B sound more like the real piano? The ABC/hr test does a better job then ABX at doing that sort of thing. > even though i am politically very liberal, as an > engineer, i am *very* conservative. No problem. > say the issue is Monster Cable. the claim > is that Monster Cable sounds better than 10 gauge lamp cable. The more reasonable claim would be that Monster Cable sounds better than 13 gauge lamp cable because much of the better Monster speaker cables are the equivalent of 13 gauge stranded wire. > now, being conservative, i am willing to grant Monster Cable the > benefit of doubt in that if people can actually hear a *difference*, i'm > willing to let their claim that they sound better go without challenge. I wouldn't call that being conservative. My flavor of conservatism would oblige me to test for better sound, even if I found that they sounded different. > but if people *cannot* hear a difference, then i am not willing > to accept, > even tentatively, that Monster Cable sounds better. That's just common sense. Sounding better implies sounding different. No difference, no better sound. Logic. > for it to sound better, it has to at the very least, sound different. Agreed. > since "better" > and "worse" is a subjective thing (like clean vinyl vs. CD), Another view is that any uncontrollable change is a degradation. IOW louder or softer or the intentional application of a tonal shift is OK, but if an inherent and irreducable result of some operation, then that change is undesirable. Since it is impossible to avoid audible changes during recording and playing back using the LP format, the difference has to be undesirable.
From: Arny Krueger on 4 May 2008 19:45
"geoff" <geoff(a)nospam-paf.co.nz> wrote in message news:M5CdnfvR7O51q4PVnZ2dnUVZ_oSunZ2d(a)giganews.com > rickman wrote: > >> If it really is a waste of time and money to use 192 kHz >> ADC and DAC, why do you think they would do it? Don't >> you think the people designing DVD equipment understand >> the economics of consumer products? >> >> Try to think about it and see if you can come up with a >> couple of reasons yourself. I'll be interested in >> hearing what you think. > > There are 3 reasons why people design and manufacture > 192KHz equipment: 1 - They imagine it makes a difference. > 2 - The technology is available, so why not > 3 - Everybody already has 44k1/48K gear, so what would we > sell them otherwise.... That is pretty well it. As time marches on, 192/24 converters with > 115 dB dynamic range are becoming jelly bean (highly inexpensive) chips. A number of years back us quality bugs smiled and ponied up about $800 for Lynx L33 cards, but now you can get pretty much the same converters and performance in < $200 eMu cards. |