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#121
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Analog is to digital as film is to video. IMO both analog audio and film
seem to create a sense of "make believe" while digital wether audio or video seems to impart a sense of urgency much like news broadcasts. Perhaps it's the way we process analog-vs-digital information in our brains or what we've been conditioned to over many years. Eric |
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#122
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I'm puzzled by all of this discussion so far. I had always understood
that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). I'm old enough to know that many of us will believe what we think we hear. So I am discounting my anecdotal impression that vinyl has more beautiful sound on it, but also more noise, and that digital is noiseless but thin. I had been anticipating that Blu-Ray or some other next generation format will finally allow sampling at a high enough stream to make music sound "warm" again. Whatever, I guess.... wrote: I'm a digiphile, but I sometimes prefer analog. Years ago, I transferred my old 8 track mults to digital and did new mixes, and I love them. On a whim while I was cleaning the studio, I broke out the old machine and listened to the original analog mult tapes. WOW! I can't describe it! |
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#123
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On Fri, 02 Sep 2005 12:49:17 -0400, Bill Van Dyk wrote:
I'm puzzled by all of this discussion so far. I had always understood that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). You have been misinformed. The CD doesn't discard any audio information whatever. Absolutely everything that was in the original audio signal is reproduced perfectly. The same cannot, unfortunately, be said for most analogue formats. I'm old enough to know that many of us will believe what we think we hear. So I am discounting my anecdotal impression that vinyl has more beautiful sound on it, but also more noise, and that digital is noiseless but thin. Wise. I had been anticipating that Blu-Ray or some other next generation format will finally allow sampling at a high enough stream to make music sound "warm" again. Whatever, I guess.... wrote: I'm a digiphile, but I sometimes prefer analog. Years ago, I transferred my old 8 track mults to digital and did new mixes, and I love them. On a whim while I was cleaning the studio, I broke out the old machine and listened to the original analog mult tapes. WOW! I can't describe it! d |
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#124
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And the bride wore her veil. And, to the groom, she was more beautiful
than he remembered. Arny Krueger wrote: "hank alrich" wrote in message Anahata wrote: People who believe vague handwaving concepts like that should look with an oscilloscope at the output of an audio D-A converter with the usual anti-aliasing filtering on it, and observe the nice smooth curves. It might come as a surprise that it doesn't appear as a series of rectangular steps. They also ought to do that with a 18 Khz singal from a fine analog deck, to see how much like the source is the playback. g Let's consider a tape running at 15 ips, given that we want to hear bass and not head bumps. ;-) In all liklihood both signals are heavily low-pass filtered, the DAC is filtered by its reconstruction filter, while the tape is likely to be filtered by its head gap losses. The square wave response of most tape machines, even the fine ones, is generally pretty grim - sometimes far worse than a DAC, because modern DACs have phase linear reconstruction filters. More likely than not, the tape will have a far larger inter-channel delay, and that delay will be wandering around due to azimuth variations as the tape tracks across the head. At 18 KHz the tape's playback will have a random, varying envelope imposed on it by a number of influences. The output of the DAC will be perfectly stable. |
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#125
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"Scott Dorsey" wrote in message
... I think analogue sounds so good for the same reason that digital sounds so good.... because the stuff going in the front end sounds so good to begin with. GIGO, as always. And this is where analog has the upper hand IMO. I think digital sounds more "accurate" but depending on the source that can be good or bad. It's not the technology that's the problem though. |
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#127
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"Bill Van Dyk" wrote in message ... I'm puzzled by all of this discussion so far. I had always understood that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). I'm old enough to know that many of us will believe what we think we hear. So I am discounting my anecdotal impression that vinyl has more beautiful sound on it, but also more noise, and that digital is noiseless but thin. I had been anticipating that Blu-Ray or some other next generation format will finally allow sampling at a high enough stream to make music sound "warm" again. Whatever, I guess.... Try SACD. |
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#128
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"Harry Lavo" wrote in message
Try SACD. Try comparing SACD to 16/44 using the procedures I suggested in another post in this thread. |
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#129
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Chel van Gennip wrote:
On Fri, 02 Sep 2005 14:00:19 +0200, Arny Krueger wrote: "William Sommerwerck" wrote in message Also a ton of people who grew up with analog, but moved to digital when digital was well enough developed to be better-sounding, are simply very thankful for digital. "Unfortunately", Arny, many of them prefer SACD to CD. Many by whose standard? Hi Rez audio formats have pretty well died in the marketplace, other than for a tiny fraction of diehard numbers-over-sound audio zealots. I see many people choose for _lower_ quality. Growing markets are MP3 players, iPods, on-line (compressed format) music sales etc. Other new trends: wireless music archiving and distribution centre at home, combinations of audio and video. In music production I see an ongoing decrease of dynamic range, even damaging excelent old recordings in re-releases. I don't expect major SACD breakthougs, e.g. at the IFA 2005 that started today in Berlin. SACD is not compatible with current trends. It's not just in audio either. Digital TV is measurably inferior to its analogue predecessor. LCD TVs are rubbish when compared to decent CRTs. Ppl are choosing convenience over quality these days. Graham |
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#130
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Ricky Hunt wrote:
"Scott Dorsey" wrote in message ... I think analogue sounds so good for the same reason that digital sounds so good.... because the stuff going in the front end sounds so good to begin with. GIGO, as always. And this is where analog has the upper hand IMO. I think digital sounds more "accurate" but depending on the source that can be good or bad. It's not the technology that's the problem though. Maybe we're getting close to an answer here ? In what way is accurate not 'better' ? Graham |
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#131
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Don Pearce wrote:
You have been misinformed. The CD doesn't discard any audio information whatever. Absolutely everything that was in the original audio signal is reproduced perfectly. The same cannot, unfortunately, be said for most analogue formats. Well, strictly speaking: The CD discards information above about 20kHz and The CD introduces quantization noise 96 dB below maximum possible output level. .... but if it's done right, that's all it does. -- Anahata -+- http://www.treewind.co.uk Home: 01638 720444 Mob: 07976 263827 |
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#132
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Also a ton of people who grew up with analog, but moved
to digital when digital was well enough developed to be better-sounding, are simply very thankful for digital. "Unfortunately", Arny, many of them prefer SACD to CD. Many by whose standard? Hi Rez audio formats have pretty well died in the marketplace, other than for a tiny fraction of diehard numbers-over-sound audio zealots. Many, as in one, two, three... many. Arny, YOU are one of the "diehard numbers-over-sound audio zealots". YOU dislike LPs because they don't measure well. YOU reject SACD simply because you don't like some of the numbers. Wake up, Arny. You're an intellectual hypocrite. Like John Atkinson, et al., you aren't interested in the truth -- whatever it might turn out to be. You're like 99.99% of all human beings -- want everything to be the way YOU think it ought to be. Double-blind testing is not "science". Science is asking the right questions, then figuring out how to get honest answers. You could stand to watch a couple of episodes of "Mythbusters". You might learn something. Have I offended you... again? You need to be offended. Along with JA and others. But you're offense-proof, because you can't think past the tiny limits of your parochial little mind. Some of the finest recordings (that is, the most natural and realistic) I've heard are on SACD. Which could have any of a large number of causes, only a few which are related to the format. Duh, I said that. But really great-sounding recordings are few and far between on any medium. The overall quality of the SACDs I've bought is surprisingly high. Overall, SACDs simply don't sound like recordings on other formats. Where the rubber hits the road is what happens when someone does a credible job of downsampling one of these great-sounding so-called high-rez recordings, and then does a bias-controlled, level matched, time-synched comparison between the purportedly low-rez transcription and the original. Well, we know it won't be /you/, because you wouldn't dare perform an experiment that threatens your world-view. I'll look through my collection and see if I have any true DSD SACD recordings that have a Red Book layer derived from the DSD source. I can transfer the CD layer directly to DAT, then sync up and compare. It won't be even a blind test (unless I can find someone who'll scramble the sources when I'm not looking), and it won't be truly fair, because the DACs will be different -- but it's a start. |
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#133
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I'm puzzled by all of this discussion so far. I had always understood
that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). You have been misinformed. The CD doesn't discard any audio information whatever. Absolutely everything that was in the original audio signal is reproduced perfectly. The same cannot, unfortunately, be said for most analogue formats. Actually, digital recording /does/ discard information. Quantization (not the sampling) removes information between the quantization steps. However, the system is set up so that the resulting error appears as random noise, which is presumably not audible as a degradation of the original sound. |
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#134
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On Sat, 03 Sep 2005 00:01:12 +0100, Pooh Bear wrote:
Maybe we're getting close to an answer here ? In what way is accurate not 'better' ? Maybe. Maybe we need to get back to the realization that it's probably COMPLETELY IMPOSSIBLE that ANY technology will EVER be invented that will allow a mechanical recording to be an EXACT duplicate of the actual performance. I think that during the "age of analog" that was taken as a given, but in the "digital age" we EXPECT nothing short of PERFECTION. Now, IF we can accept the assumption that NEITHER format can possibly be perfect. MAYBE we can believe that humans (imperfect beings that we are) might perceive some types of distortion as less objectionable than others. MAYBE? I've got LPs that sound better that the same release on CD, & I've got CDs that sound better than the same release on LP. I understand that the decisions made by the mastering engineer have a lot to do with the way the final product turns out, but in a lot of cases, I like the way a particular LP sounds IN SPITE OF the fact that I can hear the difference. With CDs (my collection anyway), the CD is either obviously better than the LP, or it's not. And I'd say that relatively speaking, my CD player is of much higher quality than my turntable. In other words, I find that I sometimes PREFER analog distortion to reality, but I have yet to ever experience a case in which I preferred digital distortion to reality. (Using the word "distortion" to identify ANY deviation from the actual performance.) I'll be the first to admit that I don't understand all the science behind all of this. I'm college educated in a (more or less) technical field, and I know enough math to accept Nyquist a gospel. And I'm always looking to be educated by anyone who wants to take the time to explain things slowly. |
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#135
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That's a good analogy IMO.
"Eric Toline" wrote in message ... Analog is to digital as film is to video. IMO both analog audio and film seem to create a sense of "make believe" while digital wether audio or video seems to impart a sense of urgency much like news broadcasts. Perhaps it's the way we process analog-vs-digital information in our brains or what we've been conditioned to over many years. Eric |
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#136
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On Sat, 03 Sep 2005 01:00:33 +0100, anahata wrote:
Don Pearce wrote: You have been misinformed. The CD doesn't discard any audio information whatever. Absolutely everything that was in the original audio signal is reproduced perfectly. The same cannot, unfortunately, be said for most analogue formats. Well, strictly speaking: The CD discards information above about 20kHz and Well, that isn't audio information, is it? And of course all analogue systems have started discarding information long before they reach as high as that frequency. The CD introduces quantization noise 96 dB below maximum possible output level. No, a dithered CD has no quantisation noise - just noise. And of course it is at a far lower level than can be obtained from any analogue medium. Just can't get away from good old physics, I'm afraid. ... but if it's done right, that's all it does. d |
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#137
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On Fri, 2 Sep 2005 17:30:00 -0700, William Sommerwerck wrote:
I'm puzzled by all of this discussion so far. I had always understood that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). You have been misinformed. The CD doesn't discard any audio information whatever. Absolutely everything that was in the original audio signal is reproduced perfectly. The same cannot, unfortunately, be said for most analogue formats. Actually, digital recording /does/ discard information. Quantization (not the sampling) removes information between the quantization steps. However, the system is set up so that the resulting error appears as random noise, which is presumably not audible as a degradation of the original sound. Well, you have this a bit wrong here. Dithering makes sure that those quantisation errors don't happen in the first place.You get just as full a set of information as you do from any analogue system, with the added advantage of much lower noise. d |
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#138
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"William Sommerwerck" wrote in
message Also a ton of people who grew up with analog, but moved to digital when digital was well enough developed to be better-sounding, are simply very thankful for digital. "Unfortunately", Arny, many of them prefer SACD to CD. Many by whose standard? Hi Rez audio formats have pretty well died in the marketplace, other than for a tiny fraction of diehard numbers-over-sound audio zealots. Many, as in one, two, three... many. Arny, YOU are one of the "diehard numbers-over-sound audio zealots". Not in this life. I'm very much about sounding good as being the ultimate standard. Numbers are just a means to an ends. YOU dislike LPs because they don't measure well. No, I don't like LPs because the LP format includes clearly audible faults that I can still hear even at my age. I probably heard them even better when I moved on to digital, some 22 years ago. I probably heard them even better when I first heard end-to-end digital, some 25 years ago. YOU reject SACD simply because you don't like some of the numbers. I own a SACD player and some SACDs. No joy. Wake up, Arny. You're an intellectual hypocrite. I don't think you've made your case for that. William. Like John Atkinson, et al., you aren't interested in the truth -- whatever it might turn out to be. I don't think you've made your case dfor that. William. You're like 99.99% of all human beings -- want everything to be the way YOU think it ought to be. Actually, I've made enough serious mistakes in life to see the weaknesses of that position - up front and personal! ;-) Double-blind testing is not "science". DBTs are often tools of science. Science is asking the right questions, then figuring out how to get honest answers. You could stand to watch a couple of episodes of "Mythbusters". You might learn something. I watch that show err, religiously! I think that due to the limitations of my DVD recorder's scheduling facility, I record it twice a week. I just watch it once, and I do skip over most (but not all) of the repeats. Have I offended you... again? You need to be offended. Trust me, I get offended regularly, but rarely on Usenet. Along with JA and others. But you're offense-proof, because you can't think past the tiny limits of your parochial little mind. My irony alarm is going off. Let me pause typing to reset it. ;-) Some of the finest recordings (that is, the most natural and realistic) I've heard are on SACD. Which could have any of a large number of causes, only a few which are related to the format. Duh, I said that. But really great-sounding recordings are few and far between on any medium. The overall quality of the SACDs I've bought is surprisingly high. Overall, SACDs simply don't sound like recordings on other formats. That would be a hypothesis for which I just suggested a test for. Where the rubber hits the road is what happens when someone does a credible job of downsampling one of these great-sounding so-called high-rez recordings, and then does a bias-controlled, level matched, time-synched comparison between the purportedly low-rez transcription and the original. Well, we know it won't be /you/, because you wouldn't dare perform an experiment that threatens your world-view. My only defense for not doing it again like I did a similar thing on PCABX back in 2001 is that I did a similar thing only better in 2001. http://www.pcabx.com/technical/sample_rates/index.htm I'll look through my collection and see if I have any true DSD SACD recordings that have a Red Book layer derived from the DSD source. I can transfer the CD layer directly to DAT, then sync up and compare. Kinda interesting, but with a whole slew of uncontrolled varaiables compared to my work in 2001. It won't be even a blind test (unless I can find someone who'll scramble the sources when I'm not looking), and it won't be truly fair, because the DACs will be different -- but it's a start. Sighted evaluations of potentially small differences? imagine the sound I make when I dismiss something out of hand. |
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#139
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"Agent 86" wrote in message
news 
Maybe we need to get back to the realization that it's probably COMPLETELY IMPOSSIBLE that ANY technology will EVER be invented that will allow a mechanical recording to be an EXACT duplicate of the actual performance. I think that during the "age of analog" that was taken as a given, but in the "digital age" we EXPECT nothing short of PERFECTION. Yup, the feed from mics suck compared to live performances. But, that's not the question at hand. Now, IF we can accept the assumption that NEITHER format can possibly be perfect. MAYBE we can believe that humans (imperfect beings that we are) might perceive some types of distortion as less objectionable than others. MAYBE? Maybe distortion in some processes can be so small that humans (imperfect beings that we are) can't perceive it at all? True. I've got LPs that sound better that the same release on CD, & I've got CDs that sound better than the same release on LP. I understand that the decisions made by the mastering engineer have a lot to do with the way the final product turns out, but in a lot of cases, I like the way a particular LP sounds IN SPITE OF the fact that I can hear the difference. With CDs (my collection anyway), the CD is either obviously better than the LP, or it's not. And I'd say that relatively speaking, my CD player is of much higher quality than my turntable. Yup, bad mastering sounds bad and some CDs are badly mastered. Next. |
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#140
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"William Sommerwerck" wrote in
message Actually, digital recording /does/ discard information. Quantization (not the sampling) removes information between the quantization steps. Not quantiation done right, which it now frequently is. If you dither the quantization properly, no data is lost per se. However practical applications of dither always seems to imply adding some noise, and that noise can mask (either perceptually or from a practical measurements standpoint) lower-level signals. However, data that is appreciably smaller than the quantization steps can and is routinely captured accurately. |
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#141
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wrote in message add some enhancements or modifications during mixdown to make the production sound better. I've also had the same experience as Vinyl Believer as far as transferring vinyl to CD. During the transfer process, some of the midrange richness disappeared. Look at what could cause problems he Inferior soundcard , agin structure problems, level optinisation, gross impedence mismatch ? geoff |
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#142
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Geoff Wood wrote:
Look at what could cause problems he Inferior soundcard , agin structure problems, level optinisation, gross impedence mismatch ? And don't forget that the Earth may not have been rotating at the proper speed that day. |
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#143
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#144
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On Sun, 04 Sep 2005 07:19:56 GMT, Chevdo wrote:
In article , says... "William Sommerwerck" wrote in message Also a ton of people who grew up with analog, but moved to digital when digital was well enough developed to be better-sounding, are simply very thankful for digital. "Unfortunately", Arny, many of them prefer SACD to CD. Many by whose standard? Hi Rez audio formats have pretty well died in the marketplace, other than for a tiny fraction of diehard numbers-over-sound audio zealots. Many, as in one, two, three... many. Arny, YOU are one of the "diehard numbers-over-sound audio zealots". Not in this life. I'm very much about sounding good as being the ultimate standard. Numbers are just a means to an ends. Arny's problem is that he doesn't understand or refuses to recognize the significance of the numbers. He doesn't understand that the spec of a device refers to its reliability to function according to the numbers, not its ability to function according to the numbers. Don Pearce makes a similar mistake when he says that signal above 20khz is not 'audio information'. 20khz is the compromise the industry standard-makers settled on for the CD format, based on leaving a bit of 'headroom' above what half the population can't hear, which is anything above 16khz. Inspite of this, most people have noticed that audio sampled, mixed and processed at 96khz sounds better, even after downsampling to 44.1khz for a CD. This is how 'holy numbers' get created and people get confused about what they mean and their significance in the 'real world'. For example, recently the JREF (John Atkinson's nemesis) covered the subject of what 'normal' human body temperature is. The number 98.6F represents quantization error because it is rounded off from 37C, but more importantly, the number 37C was arrived at by averaging a number of tests on a group of people. The same thing happens when a manufacturer presents the spec of any device or component, right down to a transistor, capacitor, diode, etc - the spec is based on averaging testing results. So what happens when one uses these numbers as 'rules' to strictly guide one's methodology? One can be guaranteed average results. You make a pretty serious error here, rather typical of those who don't understand what is going on in digital audio. You state "Inspite of this, most people have noticed that audio sampled, mixed and processed at 96khz sounds better, even after downsampling to 44.1khz for a CD." So you think that 44.1kS/s audio is sampled at 44.1kS/s do you? Well, if it were, it simply wouldn't work - alias products would be rife. No, 44.1kS/s audio is sampled at many times that frequency, filtered and downsampled to 44.1kS/s. This is called oversampling, and the need for it has been recognised since long before audio ever found its way into the digital domain.So what you claim makes no sense in terms of the technology. As for your last point - what on earth is that supposed to mean? It is wrong in many of its premises - all of the components have a minimum spec as well as a mean value. This means you aren't averaging down to mediocrity, but guaranteeing minimum performance. And finally, for your jibe at me personally - OK, I'll buy it. How far above 20kHz can you hear? More importantly, if the signal above 20kHz is removed without your knowledge, can you hear the difference. I have never met anybody who can. d |
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#146
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"Bill Van Dyk" wrote in message ... I'm puzzled by all of this discussion so far. I had always understood that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). Then you have a flawed understanding of linear PCM. geoff |
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#147
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"Chevdo" wrote in message
news:wexSe.222806$HI.189063@edtnps84 Arny's problem is that he doesn't understand or refuses to recognize the significance of the numbers. Wrong! Why don't you tell us about your years of theoretical and practical study of psychoacoustics, so I can talk about mine? He doesn't understand that the spec of a device refers to its reliability to function according to the numbers, not its ability to function according to the numbers. Irrelevant to the question at hand, which is what do the numbers mean. Don Pearce makes a similar mistake when he says that signal above 20khz is not 'audio information'. If its absence can't be heard, is it audio? 20khz is the compromise the industry standard-makers settled on for the CD format, based on leaving a bit of 'headroom' above what half the population can't hear, which is anything above 16khz. Wrong. Virtually nobody can hear the removal of signals above 16 KHz. Prove me wrong - here's where you can do the required blind tests easily: http://www.pcabx.com/technical/low_pass/index.htm http://www.pcabx.com/technical/sample_rates/index.htm Inspite of this, most people have noticed that audio sampled, mixed and processed at 96khz sounds better, even after downsampling to 44.1khz for a CD. Just tain't so. Listen for yourself, if you've got the mental and technical resources. |
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#148
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Bill Van Dyk wrote:
I'm puzzled by all of this discussion so far. I had always understood that CD's are created by sampling analog sources and discarding and reducing the resulting deluge of "information" into a reductionist format. Therefore, of coure a CD will not sound as good as an analog source (as long as it is played through a decent stereo). No, that sounds like MP3 or some other lossy format. The CD is uncompressed and full-bandwidth. I'm old enough to know that many of us will believe what we think we hear. So I am discounting my anecdotal impression that vinyl has more beautiful sound on it, but also more noise, and that digital is noiseless but thin. If this is the case for you, you should look into better converters. God knows that this was surely true with the earliest few generations of conversion. I had been anticipating that Blu-Ray or some other next generation format will finally allow sampling at a high enough stream to make music sound "warm" again. Most of the problems with CD have to do with implementation and with bad mastering. Cranking the sampling rate up won't help either of those problems. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#149
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Arny Krueger wrote:
Arny's problem is that he doesn't understand or refuses to recognize the significance of the numbers. Wrong! Why don't you tell us about your years of theoretical and practical study of psychoacoustics, so I can talk about mine? Please, spare us. |
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#150
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SSJV wrote:
Cute thought except for the small matter that it's just plain wrong. Just his theory. Well, again, No. It's NOT a theory at all. It's his own postulation or guess, not even a well-laid out HYPOTHESIS at that. ________________ Sorry dudes. Many of you here are showing a very POOR understanding of the digital process and it's limitations. First off get this idea now: Nyquist is Bull****! The theory as usually stated totally ignores PHASE! The usual statement is that sampling at or below the nyquist rate allows you to mathematically regenerate the original waveform exactly from the samples. A TOTALLY false statement! It only becomes a true statement if the phase of the waveform is correct. Dig. Sample a high frequency sinewave right in the center of each positive and negative hump. So you know it's a sine wave and you know it's magnitude so you could (theoretically) regenerate that wave from that information. But now sample that SAME waveform right at the zero-crossings! Your samples are now all ZERO! And yet people here are telling us they are going to regenerate a waveform exactly from NO information. Not so, CD breath. OK. So one simply does more samples so this phase error is less. Double the sample rate and now the uncertainly becomes much less than zero to 100%. Double again and the max error is reduced still further. But there is always a practical consideration. PLAYING TIME! The idea of a "one song" CD has not yet caught on much. So it's little wonder that the standard CD standards are cut back to the minimum. And it's no wonder that CDs have that harsh high end on some material. But the plus is the purity of the digital signal with lack of noise and other advantages tends to offset the minor harshness a lot. But that is apples and oranges. The fact that digital media has lots of convenience and low noise doesn't change the fact they are (usually) under-sampled. And as for SSJV, his head is very much where the sun don't shine. (Usually found to be the case when people start spouting how other people are just plain wrong! Usually things are not so clear in real life as "right" and "wrong") Fact is that HOW you sample a wavefome DOES matter! The best methods generally revolve around some scheme that integrate the values BETWEEN sample points. The CHEAP methods generally involve sampling at a point and throwing the "dark spaces" away. One more reason why high quality digital gear often sounds better than cheap stuff. But once again "phase" rears its ugly head. Suppose for example you have a waveform with a sharp high frequency spike in it. (cymbal sound, say) If you sample right ON the spike you get a high sample value. But if you sample on both sides of it, you get samples as if the spike weren't there at all. Again it all depends upon the phase or more correctly on the timing of the samples vs the waveforms. But if you are using an integrating method, You get an error, but the spike is never completely lost. But as before if one samples fast enough all these problems begin to go away. I know you are going to say, hey, these things are all above the range of human hearing so they don't matter. But they do matter. Studies have been run that show that sounds that are above what people can hear ARE heard in the sense that people can detect a difference in the subtle character of the playback if these "unhearable" sounds are there or not! There are lots of theories, but the idea basically is that "unhearable" sounds of say a cymbal somehow cross-modulate with lower frequency "hearable" sounds to change the overall character of what you can hear. Happily the world is moving away from lots of playing time into higher sampling rates. DVDs are thus a huge advance in this regard (except that in DVDs they've moved all these sampling problems into the VIDEO realm!) So IF we carefully word our statement here and ask, if LPs can sound "better" than CD's, we might conclude due to the sampling problems that they can. But one ALSO must realize that LPs have problems too, even if we put noise etc. aside. One such problem is that the vinyl actually flexes under the forces generated by the needle which distorts the high frequency response of the medium. BUT I think you can see that this LP distortion to the human ear will likely sound much less objectionable than the "harsh" bouncing phase errors of an undersampled CD. Thus even though both media might be equally less "accurate" at high freqencies, people often conclude that the LP "sounds better" and yeah, it probably does. I think a number of people in this thread have more or less taken this position which takes into account how equally "innacurate" signals may not sound equally objectionable to the human ear. Benj |
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#151
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wrote in message
oups.com I've also had the same experience as Vinyl Believer as far as transferring vinyl to CD. During the transfer process, some of the midrange richness disappeared. If you have concerns about losing sound quality during digital transfers you should carefully scrutinize your digital interface. One way to examine the sound quality of your digital audio interface this is to loop its input to its output, and re-record some excellent digital music through it. Level-match, time-synch your re-recording with the origional with your DAW software. Compare the source with the original using the comparator sofware you can freely download from www.pcabx.com . Here is a worked-example of a digital interface that changes the sound quality of music that it re-records: http://www.pcabx.com/product/ct4830/index.htm Here is a worked-example of a digital interface that makes minimal changes the sound quality of music that it re-records: http://www.pcabx.com/product/cardd_deluxe/index.htm |
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#152
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Sorry dudes. Many of you here are showing a very POOR understanding of
the digital process and it's limitations. First off get this idea now: Nyquist is Bull****! The theory as usually stated totally ignores PHASE! The usual statement is that sampling at or below the nyquist rate allows you to mathematically regenerate the original waveform exactly from the samples. A TOTALLY false statement! It only becomes a true statement if the phase of the waveform is correct Dig. Sample a high frequency sinewave right in the center of each positive and negative hump. So you know it's a sine wave and you know it's magnitude so you could (theoretically) regenerate that wave from that information. Not so. EXACTLY two samples per cycle is amplitudinally ambiguous. You don't know "where" along the waveform they've occurred. But now sample that SAME waveform right at the zero-crossings! Your samples are now all ZERO! And yet people here are telling us they are going to regenerate a waveform exactly from NO information. Not so, CD breath. Sorry, but Nyquist is correct. You've mistated it, then given an example of the mis-statement. The Nyquist criterion requires sampling GREATER THAN twice the highest frequency. Sampling at twice the highest frequency produces exactly the amibiguity you describe. |
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#153
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#154
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#155
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No, it doesn't ignore phase, and the rest of your post demonstrates a
classic misunderstanding of the way PCM sampling works. Google for "reconstruction filter" and be englightened. Another misunderstanding... There's no such thing as a "reconstruction filter". The samples contain the original signal, unmodified. If you played the samples through a distortionless speaker, you would hear the original sound, unaltered. |
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#156
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wrote:
Sorry dudes. Many of you here are showing a very POOR understanding of the digital process and it's limitations. First off get this idea now: Nyquist is Bull****! The theory as usually stated totally ignores PHASE! The usual statement is that sampling at or below the nyquist rate allows you to mathematically regenerate the original waveform exactly from the samples. It does not ignore phase at all. Go back and read the original Nyquist paper. A TOTALLY false statement! It only becomes a true statement if the phase of the waveform is correct. Dig. Sample a high frequency sinewave right in the center of each positive and negative hump. So you know it's a sine wave and you know it's magnitude so you could (theoretically) regenerate that wave from that information. But now sample that SAME waveform right at the zero-crossings! Your samples are now all ZERO! And yet people here are telling us they are going to regenerate a waveform exactly from NO information. Not so, CD breath. Right, this happens if your sample rate is an even multiple of the frequency being sampled. You can't do that. The Nyquist rate is twice the highest frequency of interest, and the sampling rate must be _higher_ than that. Only a tiny amount higher, but higher. OK. So one simply does more samples so this phase error is less. Double the sample rate and now the uncertainly becomes much less than zero to 100%. Double again and the max error is reduced still further. But there is always a practical consideration. PLAYING TIME! The idea of a "one song" CD has not yet caught on much. So it's little wonder that the standard CD standards are cut back to the minimum. And it's no wonder that CDs have that harsh high end on some material. But the plus is the purity of the digital signal with lack of noise and other advantages tends to offset the minor harshness a lot. But that is apples and oranges. The fact that digital media has lots of convenience and low noise doesn't change the fact they are (usually) under-sampled. I think you might want to go back and read Gabe's discussion of the sampling theory in the FAQ, because it's clear you're missing out on how the process works. Fact is that HOW you sample a wavefome DOES matter! The best methods generally revolve around some scheme that integrate the values BETWEEN sample points. The CHEAP methods generally involve sampling at a point and throwing the "dark spaces" away. One more reason why high quality digital gear often sounds better than cheap stuff. But once again "phase" rears its ugly head. This is also totally incorrect, and again you might want to go back and read the FAQ on the subject. Suppose for example you have a waveform with a sharp high frequency spike in it. (cymbal sound, say) If you sample right ON the spike you get a high sample value. But if you sample on both sides of it, you get samples as if the spike weren't there at all. Again it all depends upon the phase or more correctly on the timing of the samples vs the waveforms. But if you are using an integrating method, You get an error, but the spike is never completely lost. But as before if one samples fast enough all these problems begin to go away. All these problems go away with anti-aliasing filters. In this modern age we use oversampling so most of the anti-aliasing is done in the digital domain. I know you are going to say, hey, these things are all above the range of human hearing so they don't matter. But they do matter. Studies have been run that show that sounds that are above what people can hear ARE heard in the sense that people can detect a difference in the subtle character of the playback if these "unhearable" sounds are there or not! There are lots of theories, but the idea basically is that "unhearable" sounds of say a cymbal somehow cross-modulate with lower frequency "hearable" sounds to change the overall character of what you can hear. Can you site any of these studies? I haven't seen a good one in either direction. Hint: the Kanagawa Institute studies are not good ones. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#157
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William Sommerwerck wrote:
No, it doesn't ignore phase, and the rest of your post demonstrates a classic misunderstanding of the way PCM sampling works. Google for "reconstruction filter" and be englightened. Another misunderstanding... There's no such thing as a "reconstruction filter". The samples contain the original signal, unmodified. If you played the samples through a distortionless speaker, you would hear the original sound, unaltered. No, if you played the samples one after the other without any filtering, you would hear the original sample with a lot of high frequency trash added. That's why we have reconstruction filters. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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#158
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wrote:
Studies have been run that show that sounds that are above what people can hear ARE heard in the sense that people can detect a difference in the subtle character of the playback Yeah, and other studies have shown that people don't hear a lick of difference between a recording that includes ultrasonics and one that doesn't. Test results continue to contradict each other today. It seems likely that poor controls are the reason. Studies schmuddies. -- "It CAN'T be too loud... some of the red lights aren't even on yet!" - Lorin David Schultz in the control room making even bad news sound good (Remove spamblock to reply) |
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#159
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Another misunderstanding... There's no such thing as a "reconstruction
filter". The samples contain the original signal, unmodified. If you played the samples through a distortionless speaker, you would hear the original sound, unaltered. No, if you played the samples one after the other without any filtering, you would hear the original sample with a lot of high frequency trash added. That's why we have reconstruction filters. There would be high-frequency "trash" but it would be inaudible (ultrasonic). It's okay to say "low-pass" filter. But it is NOT a reconstruction filter. You cannot reconstruct what is, and always has been, present. |
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#160
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On 29 Aug 2005 07:23:07 -0700, "Nate Najar"
wrote: I don't mean to start what could turn into a nasty argument, but I was wodnering something. Last night I was listening to one of my favorite records- Tom Jobim and Elis Regina "Elis and Tom". I have the lp and also the cd. I was listening to the lp and even though my copy crackles like a bowl of rice krispies, I couldn't believe how good it sounded. I'm trying to think of words to describe it- the best I can come up with would be transparent, detailed and alive. It just sounded very natural to me. Now I own this recording on cd and so i grabbed it and compared the two. The cd definitely sounds good, but it didn't sound near as lifelike as the vinyl. Am I dreaming? what is it I'm hearing? You've got some digital recording gear? Make a simple recording off the vinyl and burn a CD. How's it compare with the commercial CD, which was probably "digitally remastered" or some such. |
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