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#81
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High-end audio
The issue is whether the noise already in a signal -- regardless
of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. Dither is simply noise that is added to the signal, so it is there ready when the quantization occurs. It matters not a jot how long before quantization the noise got there. If it is added at the microphone, it is exactly the same as if it was added a nanosecond before quantization. All that matters is that it is a signal free from correlation. Noise, in other words. Forgive me, Mr Pearce, but that has nothing to do with what I said. Please read what I wrote. |
#82
Posted to rec.audio.pro
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High-end audio
On Fri, 23 Mar 2012 13:30:19 -0700, "William Sommerwerck"
wrote: The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. Dither is simply noise that is added to the signal, so it is there ready when the quantization occurs. It matters not a jot how long before quantization the noise got there. If it is added at the microphone, it is exactly the same as if it was added a nanosecond before quantization. All that matters is that it is a signal free from correlation. Noise, in other words. Forgive me, Mr Pearce, but that has nothing to do with what I said. Please read what I wrote. To the contrary - it goes to the heart of it. All noise that hits the A to D is, as you say, already in the signal. That includes artificial dither, people breathing, traffic outside in the street. It is the sum of all that noise which provides the dither. As long as it is large enough to bridge the gap between adjacent sampling levels, it will do the job. That is all that is required of it. Any more is unnecessary, but certainly won't stop it working. Do the maths if you remain unconvinced. d |
#83
Posted to rec.audio.pro
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High-end audio
петак, 23. март 2012. 20.44.45 UTC+1, Ron Capik је написао/ла:
On 3/23/2012 4:57 AM, Marc Wielage wrote: As I understand the law, the thread needs to evolve to that point, and forcing the point is a violation. [YMMV] Unfortunately, group was reluctant to accept the only correct answer, the first one from Mike Rivers. This topic does not belong here. Fortunately, there are some great and sane people here who drove the thread into something interesting and applicable. However, usual suspects are determined for the oposite. Just out of nowhere dithering emerged as side topic, soon enough ... Is there anybody here interested in runing studio, being hired to record/ mix bands, music, ..., for real, ... |
#84
Posted to rec.audio.pro
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High-end audio
William Sommerwerck wrote:
"Scott Dorsey" wrote in message ... William Sommerwerck wrote: For the time being, I remain unconvinced. Dither is a good idea and it doesn't hurt to use it. I said that! The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would to see an explanation that goes beyond hand-waving. If the noise floor weren't random to the extent decent dither is random, would it really do dither's job? -- shut up and play your guitar * http://hankalrich.com/ http://www.youtube.com/walkinaymusic http://www.sonicbids.com/HankandShaidri |
#85
Posted to rec.audio.pro
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High-end audio
"Marc Wielage" wrote in message .com... Can't somebody just yell "HITLER" ... You just did. Trevor. |
#86
Posted to rec.audio.pro
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High-end audio
wrote in message news:9670737.1461.1332520127195.JavaMail.geo-discussion-forums@vbux23... I think it's mainly ignorance, and also being brainwashed by audio salespeople and magazines. Yes, I've been told more than once "I don't want my living room to look like a recording studio" and I understand that. But if someone has $100k invested in "gear" and doesn't have a dedicated room, or doesn't care enough to obtain what their system is capable of, their priorities are really screwed up IMO. Well if they've spent $100k then that probably goes without saying. But it's simple, bragging rights come from the equipment itself, not it's sound. And they don't want to spoil the $1million decor with room treatments for sound. However some billionaires DO have a proper acouticaly designed dedicated listening rooms. The room costs *FAR* more than $100k though, so that's the problem for mere millionaires :-) Trevor. |
#87
Posted to rec.audio.pro
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High-end audio
"hank alrich" wrote in message ... If the noise floor weren't random to the extent decent dither is random, would it really do dither's job? If it's not random you shouldn't call it "noise", but an unwanted signal. eg. some people may call hum, "noise", but that's just a sloppy definition. Trevor. |
#88
Posted to rec.audio.pro
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High-end audio
On 3/23/2012 12:30 PM, William Sommerwerck wrote:
Wouldn't truly random noise not require dither? Wouldn't it be self-dithering? Boy! Is that ever a question for the philosophers! That's in the same category as "If a tree falls in the forest, can you hear the sound of one hand clapping?" -- "Today's production equipment is IT based and cannot be operated without a passing knowledge of computing, although it seems that it can be operated without a passing knowledge of audio." - John Watkinson http://mikeriversaudio.wordpress.com - useful and interesting audio stuff |
#89
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High-end audio
Trevor writes:
Well if they've spent $100k then that probably goes without saying. But it's simple, bragging rights come from the equipment itself, not it's sound. And they don't want to spoil the $1million decor with room treatments for sound. People with this type of personality not only do not care about the sound, but are afraid to say that a system doesn't sound good to them. So when the dominant wealthy individual with the expensive equipment says that the sound is great, his non-wealthy and sycophantic friend will nod his head in agreement, even though he cannot seem to hear the fabulous sound that his alpha friend claims to hear. He doesn't want to seem dumb or uneducated, so he assumes that he's just missing something and pretends that he hears fabulous sound, too. It's like the emperor's new clothes. |
#90
Posted to rec.audio.pro
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High-end audio
"Luxey" wrote in message news:23826693.1455.1332518730099.JavaMail.geo-discussion-forums@vbtv42... William Sommerwerck wrote" Not at all. I understand that. See below. One of my points is that how noise that is comparable in level to the signal itself randomize quantization errors that are much lower in level? Seams your question is if the low level signal is actually dithering higher level noise, instead of being vice versa? Dither almost always ends up being used with higher level signals, so whether that signal is noise or other, doesn't matter. Dither is only needed to randomize quantization error, whose size is the size of a LSB. However, quantization conserves energy, so the noise in the signal is not diminished when it becomes the source of dither. What does happen is that the portion of the noise that is engaged in randomizing the quantization error changes from being one random signal to a different, but still random signal. IOW you can take the noise floor of the signal, and split it into two pieces. One piece is changed by its application as dither, and the other piece is unchanged. The portion that was used for dither remains random, but its spectrum and probability distribution may be changed somewhat. Whether there is an audible difference depends on the ratio of the sizes of the two pieces. The piece that gets changed is about twice the amplitude of the LSB. If the noise floor is say 10 dB higher, the part affected by quantization is very likely to be completely masked by the larger portion of the noise floor, which is unchanged. |
#91
Posted to rec.audio.pro
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High-end audio
On Mar 22, 8:59*am, "Arny Krueger" wrote:
"William Sommerwerck" wrote in message ... "Arny Krueger" wrote in message m... The counterpoint is that virtually every real world audio signal has enough noise to dither itself. Enough of it comes from the analog domain, which *just isn't that clean compared to 16 bits. I'm not sure this is correct. But I'm not going to argue the point before doing some checking. Funny story that involves your good buddy Mr. JA. He wrote a glowing SP review of a Meridian ADC with selectable dither, centerpieced by his experiences transcribing one of his analog master tapes. In his sighted evaluations he seemed to find a *different poetic description of every different dither that the Meridian added. The article in which I discuss this situation in somewhat different terms as described by Arny Krueger can be found at http://www.stereophile.com//asweseeit/523/index.html . *I did a little study of the situation and found that as a rule, the analog tape had 10s of dB more noise, even on an fractional-octave basis. As I discuss in the article, there was no "analog tape"; the source was 20-bit files that had been recorded on a Nagra-D recorder. John Atkinson Editor, Stereophile |
#92
Posted to rec.audio.pro
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High-end audio
On Saturday, 24 March 2012 20:01:51 UTC+1, Arny Krueger wrote:
"Luxey" wrote in message news:23826693.1455.1332518730099.JavaMail.geo-discussion-forums@vbtv42... William Sommerwerck wrote" Not at all. I understand that. See below. One of my points is that how noise that is comparable in level to the signal itself randomize quantization errors that are much lower in level? Seams your question is if the low level signal is actually dithering higher level noise, instead of being vice versa? Dither almost always ends up being used with higher level signals, so whether that signal is noise or other, doesn't matter. Dither is only needed to randomize quantization error, whose size is the size of a LSB. However, quantization conserves energy, so the noise in the signal is not diminished when it becomes the source of dither. What does happen is that the portion of the noise that is engaged in randomizing the quantization error changes from being one random signal to a different, but still random signal. IOW you can take the noise floor of the signal, and split it into two pieces. One piece is changed by its application as dither, and the other piece is unchanged. The portion that was used for dither remains random, but its spectrum and probability distribution may be changed somewhat. Whether there is an audible difference depends on the ratio of the sizes of the two pieces. The piece that gets changed is about twice the amplitude of the LSB. If the noise floor is say 10 dB higher, the part affected by quantization is very likely to be completely masked by the larger portion of the noise floor, which is unchanged. Please, keep me out of your conversation with your friend William and do not quote my post if you are not responding to one. |
#93
Posted to rec.audio.pro
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High-end audio
On Saturday, March 24, 2012 7:11:23 PM UTC-4, Soundhaspriority wrote:
This is all synth, am I correct? If it isn't, it sounds a lot like synth, delivered as an mp3. No, it's not all synths. There are live acoustic and electric guitars, a live cello section, and sampled drums (which started life as Wave file recordings). But why do you believe that music made using synthesizers isn't valid for testing the audibility of dither? ... a recording is made with such care, and delivered to the consumer in a format unblemished by compression, so that the effect of dither becomes apparent. I'll make you the same offer I make everyone else: Please create your own example file showing that dither makes an audible difference for music recorded at normal levels, and post it for all to hear. I know you won't do this because you can't, just as others have never been able to create such a file to prove their beliefs. What bothers me most is this is so common. Someone makes a claim, such as dither is audible on typical pop music recorded at a normal level. I ask for proof, which should be simple if dither actually mattered. But the person never posts proof (they're always too busy), yet they continue to hold the same beliefs. Tell you what Bob, if you can show that dither is audible on any pop music type mix recorded at a sensible level, I promise I will change my opinion immediately and delete the Dither article from my web site. But if you can't, I expect you to acknowledge here that you were unable to create a compelling example, and stop posting publicly that dither makes a difference for most music. Deal? --Ethan |
#94
Posted to rec.audio.pro
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High-end audio
The lack of dither should be audible on solo flute.
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#95
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High-end audio
Mxsmanic wrote:
Scott Dorsey writes: I suggest you actually try this instead of just pretending to have done so. I actually tried it. Take an uncompressed file like a .wav, put it into a video container file and upload it. What comes back won't be anything like what you sent up. I was comparing the files he sent me, which he said were the original and the YouTube versions. If they were truly what he told me they were, there was no significant degradation in the YouTube audio. No. Try it yourself, with your own file. Start out with uncompressed clean audio so you know where you're beginning. Then when you get it back, subtract it from the original. It's going to take you some time to get the two lined up perfectly so they subtract at all, but you'll find that at no point do they subtract reasonably well. The difference file is quite enlightening to listen to. What's interesting is that the same thing is apt to happen to the video as well as to the audio. Youtube uses perceptual encoding for both, so for they audio they basically throw away anything that the algorithm thinks won't be audible. What gets thrown away is between 70% and 90% of the actual data stream going up if you're sending up uncompressed audio. That's how all lossy compression for audio and video generally works these days. Otherwise YouTube would not be able to compressed video by nearly 500 to 1 with so few artifacts. Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#96
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High-end audio
Scott Dorsey writes:
Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. I look forward to the day when everyone has sufficient disk space and network bandwidth and processor power to handle all audio and video uncompressed. Audio is probably already there, as long as you don't need to send it to anyone over a network, but video has a long way to go, with its 1000-times-greater requirements. |
#97
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High-end audio
Scott Dorsey wrote:
wrote: Scott Dorsey writes: I suggest you actually try this instead of just pretending to have done so. I actually tried it. Take an uncompressed file like a .wav, put it into a video container file and upload it. What comes back won't be anything like what you sent up. I was comparing the files he sent me, which he said were the original and the YouTube versions. If they were truly what he told me they were, there was no significant degradation in the YouTube audio. No. Try it yourself, with your own file. Start out with uncompressed clean audio so you know where you're beginning. Then when you get it back, subtract it from the original. It's going to take you some time to get the two lined up perfectly so they subtract at all, There is usually quiet at the first, so add a single-sample pulse. Use that as a slate to line 'em up. if there's no quiet, add a second or so of zero samples. Add the pulse, then encode, then use the pulse to line them up. It may be delayed a fraction of a sample depending on the codec. but you'll find that at no point do they subtract reasonably well. The difference file is quite enlightening to listen to. What's interesting is that the same thing is apt to happen to the video as well as to the audio. Youtube uses perceptual encoding for both, so for they audio they basically throw away anything that the algorithm thinks won't be audible. What gets thrown away is between 70% and 90% of the actual data stream going up if you're sending up uncompressed audio. That's how all lossy compression for audio and video generally works these days. Otherwise YouTube would not be able to compressed video by nearly 500 to 1 with so few artifacts. Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. --scott -- Les Cargill |
#98
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High-end audio
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#99
Posted to rec.audio.pro
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High-end audio
Peter Larsen wrote:
wrote: I'll make you the same offer I make everyone else: Please create your own example file showing that dither makes an audible difference for music recorded at normal levels, and post it for all to hear. Please define "showing", I may be lame-brained tonight, but I don't quite understand how to meet your requirements. What is it you ask for? I'd be more interested in hanging with someone like Dave Collins in his mastering suite and have him show me how he chooses a specific dither at the final stage of a CD mastering project to see if I can hear it in that context. -- shut up and play your guitar * http://hankalrich.com/ http://www.youtube.com/walkinaymusic http://www.sonicbids.com/HankandShaidri |
#100
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High-end audio
"William Sommerwerck" wrote in message ... "High-end" audio has been around at least 60 years, though it was not called that. In fact, it arguably extends back to the 30s, with E H Scott making horribly expensive radio receivers, and Avery Fisher assembling custom systems. I've only seen the E.H. Scott stuff in museums and private collections, but it is a sight to see. Build quality up the ... Its modern incarnation began with Macintosh and Marantz products after WWII, which most people could not afford. $250 power amps and preamps were beyond the reach of most listeners. (I remember this very well.) I think that Mac 075s were under $200 in their day. 275s were under $400 if memory serves. You didin't mention the Bozak, JBL and larger EV systems of the day. Two words: JBL Paragon. The high end really got going when Crown introduced the DC-300, a $545 transistor power amplifier, in the early 60s. It was one of the first "good" transistor amps, not only in having decent sound, but not blowing up. Though intended as an industrial amplifier, it sold very well to consumers. I don't recall it costing that much. What happened since then is too complex to explain in a brief post. People got greedy and things got crazy - magic wires, $10,000 speakers with 5 inch woofers, outlandish turntables and cartrdiges that didn't work better than what Shure and Thorens sold for a few $100. |
#101
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High-end audio
wrote in message news:9670737.1461.1332520127195.JavaMail.geo-discussion-forums@vbux23... On Friday, March 23, 2012 5:04:29 AM UTC-4, Marc Wielage wrote: Unfortunately, there's no way to package room acoustics and sell them for $99.95 (more like $995.95) like you can an expensive cable. Well, some expensive cables sell for $5,000 each, and you can buy a room full of great acoustic treatment for the cost on a stereo pair of wires like that. I've wondered if anybody actually bought those. I see stuff like that as trend-setters that helps sell $200 wires. Holt was dismayed and unhappy that so few people grasped the importance of the room itself. Holt and Atkinson were very different people. |
#102
Posted to rec.audio.pro
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High-end audio
"William Sommerwerck" wrote in message ... "Scott Dorsey" wrote in message ... William Sommerwerck wrote: For the time being, I remain unconvinced. Dither is a good idea and it doesn't hurt to use it. I said that! The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would to see an explanation that goes beyond hand-waving. Clear evidence William that you know nothing about the block diagram of an ADC that uses external dither. I'll give you a hand. http://www.analog.com/library/analog...adc_noise.html Figure 5a. What's the difference in terms of processing between a noise coming in with the input signal, and noise coming in from the noise generator? None! |
#103
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High-end audio
"Arny Krueger" wrote in message
... Holt and Atkinson were very different people. Indeed. Thank you for acknowledging that. |
#104
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High-end audio
"William Sommerwerck" wrote in message ... The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. Dither is simply noise that is added to the signal, so it is there ready when the quantization occurs. It matters not a jot how long before quantization the noise got there. If it is added at the microphone, it is exactly the same as if it was added a nanosecond before quantization. All that matters is that it is a signal free from correlation. Noise, in other words. Forgive me, Mr Pearce, but that has nothing to do with what I said. Please read what I wrote. William, this is one of the most irrational things I've read lately. Mr. Pierces comment exactly addresses your question. You're just too mentally knackered to perceive it! |
#105
Posted to rec.audio.pro
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High-end audio
"hank alrich" wrote in message ... William Sommerwerck wrote: "Scott Dorsey" wrote in message ... William Sommerwerck wrote: For the time being, I remain unconvinced. Dither is a good idea and it doesn't hurt to use it. I said that! The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would to see an explanation that goes beyond hand-waving. If the noise floor weren't random to the extent decent dither is random, would it really do dither's job? Good insight. However, the requirements for effective dither are actually pretty lax, especially if you are willing to add more noise than necessary. For example, the most effective dither is noise whose amplitude distribution or density is like a triangle. This is called TPDF dither. TPDF dither gives you full randomization of quantization distortion with the smallest possible amount of added dither noise. OK, lets say that the noise is not TPDF, but instead Gaussian - you know the amplitude distribution is like a bell-shaped curve. Crank Gaussian noise up a bit, and it also gives you full randomization quantization distortion. TPDF noise is the most efficient, but if you are willing to tolerate a little more noise, Gaussian noise still works. Extrapolate that to the noise that is already present in every microphone's and mic preamp's output. For reasons related to statistical theory, real world noise tends very strongly to be Gaussian. Since more of it than the minimum you need fro good randomization is there, the fact that it is a little inefficient causes no difficulty. |
#106
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High-end audio
"Arny Krueger" wrote in message
... The issue is whether the noise already in a signal -- REGARDLESS OF LEVEL -- [emphasis added] automatically dithers it. I don't believe it does. I would to see an explanation that goes beyond hand-waving. Clear evidence William that you know nothing about the block diagram of an ADC that uses external dither. I'll give you a hand. http://www.analog.com/library/analog...adc_noise.html Figure 5a. What's the difference in terms of processing between a noise coming in with the input signal, and noise coming in from the noise generator? None! 1. Locate concrete wall. 2. Bang head against it repeatedly, until blood flows copiously. 3. Back away from wall, taking "pleasure" in the reduced pain. I have many failings, but I know how to read, and how to understand what I read. Most people do not. The operative language is "regardless of level" (see above), which you and everyone else conveniently ignore. How can you have possibly missed this? How can it be misunderstood? Why is it necessary to have to explain things that have been clearly stated? OF COURSE it doesn't matter "where" the dither is applied. THAT ISN'T THE ISSUE. It's the question of the correct or appropriate level. |
#107
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High-end audio
"Trevor" wrote in message ... "hank alrich" wrote in message ... If the noise floor weren't random to the extent decent dither is random, would it really do dither's job? If it's not random you shouldn't call it "noise", but an unwanted signal. eg. some people may call hum, "noise", but that's just a sloppy definition. It turns out that certain non-noise signals that are generally unwanted can also decorrelate quantization distortion. Ultrasonic tones can work a treat. |
#108
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High-end audio
"Arny Krueger" wrote in message
... "William Sommerwerck" wrote in message ... The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. Dither is simply noise that is added to the signal, so it is there ready when the quantization occurs. It matters not a jot how long before quantization the noise got there. If it is added at the microphone, it is exactly the same as if it was added a nanosecond before quantization. All that matters is that it is a signal free from correlation. Noise, in other words. Forgive me, Mr Pearce, but that has nothing to do with what I said. Please read what I wrote. William, this is one of the most irrational things I've read lately. Mr. Pierces comment exactly addresses your question. IT DOES NOT. It ignores my question, COMPLETELY. You're just too mentally knackered to perceive it! No, Arny, you are NOT reading what I wrote! READ IT! The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. What part of "regardless of level" don't you understand? |
#109
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High-end audio
wrote in message ... On Mar 22, 8:59 am, "Arny Krueger" wrote: "William Sommerwerck" wrote in message ... "Arny Krueger" wrote in message m... The counterpoint is that virtually every real world audio signal has enough noise to dither itself. Enough of it comes from the analog domain, which just isn't that clean compared to 16 bits. I'm not sure this is correct. But I'm not going to argue the point before doing some checking. Funny story that involves your good buddy Mr. JA. He wrote a glowing SP review of a Meridian ADC with selectable dither, centerpieced by his experiences transcribing one of his analog master tapes. In his sighted evaluations he seemed to find a different poetic description of every different dither that the Meridian added. The article in which I discuss this situation in somewhat different terms as described by Arny Krueger can be found at http://www.stereophile.com//asweseeit/523/index.html . I did a little study of the situation and found that as a rule, the analog tape had 10s of dB more noise, even on an fractional-octave basis. As I discuss in the article, there was no "analog tape"; the source was 20-bit files that had been recorded on a Nagra-D recorder. I have no recollection of ever reading that article. But, I've read 100,000's of articles and believe it or not, my memory going back 18 years is not perfect. John might change the article we talked about in the conversation I recall to another one that we may have discussed at a different time for whatever reason, including flawed memory like mine. Unlike John I don't have his library of articles at my disposal. It actually doesn't matter, because the major noise source was the recording itself. |
#110
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High-end audio
"Soundhaspriority" wrote in message ... wrote in message news:11844376.419.1332349048567.JavaMail.geo-discussion-forums@vbht7... On Wednesday, March 21, 2012 9:36:46 AM UTC-4, anahata wrote: As for Ethan's "Audio Myths" video, I saw that a couple of weeks ago and there's a lot of good stuff there, though I'm not sure sure everyone would agree with his views about the (un)importance of dither. Download and play the files from this Dither article, then email me your guesses as to which are dithered and which are not: This is all synth, am I correct? If it isn't, it sounds a lot like synth, delivered as an mp3. When CD was young, my gravitation was towards new-age synthetic music, because it sounded a heck of a lot better than CD recordings of orchestral and chamber recordings. As enhanced techniques of recording and production arrived, in the form of 20 bit capture, and then, noise-shaping dither, I reveled in the experience of "Being There", where "There" is Carnegie Hall, or the upstairs Weill Recital Hall. Ethan, your statement, as applied to the musical material of the experiment, is probably true. Yet I find myself rather unsympathetic to the message. The message encourages people to think a certain way, and it is unfortunately the case that many nave home recordists are likely to misinterpret the message, resulting in application you did not intend. Perhaps you should write another article to rebalance the message, one in which a recording is made with such care, and delivered to the consumer in a format unblemished by compression, so that the effect of dither becomes apparent. Probably related to the fact that Sounhaspriority's comments are frequently lost in the weeds, while Ethan's are generally spot-on. |
#111
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High-end audio
"Soundhaspriority" wrote in message ... wrote in message news:30906534.679.1332690267173.JavaMail.geo-discussion-forums@vbbdy9... [snip] Tell you what Bob, if you can show that dither is audible on any pop music type mix recorded at a sensible level, I promise I will change my opinion immediately and delete the Dither article from my web site. But if you can't, I expect you to acknowledge here that you were unable to create a compelling example, and stop posting publicly that dither makes a difference for most music. Deal? --Ethan Ethan, I didn't use the word "most." How can this be discussed if you attribute to me a statement that I did not make, as in "that dither makes a difference for most music" ? It seems to be implied that one can think of music in terms of quantity. I don't; it is entirely a qualitative experience for me. But I'll give you your space. Whatever kind of recording "Lullaby" represents, dither doesn't matter. Nothing matters. Don't take it personally, because the lullaby as a genre is not one of my interests -- unless it's "Lullaby of Birdland." The expected sloughing and obfuscation. |
#112
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High-end audio
"William Sommerwerck" wrote in message ... The lack of dither should be audible on solo flute. Record that solo flute in an anechoic chamber with a NC 0 noise floor, and a lack of dither may be audible. OTOH, there is a certain amount of noise-like sound related to the turbulence of the air blowing through the flute that might self-dither it enough. At any rate, record that solo flute at a nominal distance in a NC30 concert hall, and self-dithering is a slam dunk. |
#113
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High-end audio
"William Sommerwerck" wrote in message ... "Arny Krueger" wrote in message ... The issue is whether the noise already in a signal -- REGARDLESS OF LEVEL -- [emphasis added] automatically dithers it. I don't believe it does. I would to see an explanation that goes beyond hand-waving. Clear evidence William that you know nothing about the block diagram of an ADC that uses external dither. I'll give you a hand. http://www.analog.com/library/analog...adc_noise.html Figure 5a. What's the difference in terms of processing between a noise coming in with the input signal, and noise coming in from the noise generator? None! 1. Locate concrete wall. 2. Bang head against it repeatedly, until blood flows copiously. 3. Back away from wall, taking "pleasure" in the reduced pain. I have many failings, but I know how to read, and how to understand what I read. Most people do not. The operative language is "regardless of level" (see above), which you and everyone else conveniently ignore. No ignorance, just an appreciation for the weakness of your argument. You need more qualifiers than just level to build a working hole in the logic of self-dithering. |
#114
Posted to rec.audio.pro
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High-end audio
"Soundhaspriority" wrote in message ... Or the sound of rosin on a bow. Record that violin in an anechoic chamber with a NC 0 noise floor, and a lack of dither may be audible. OTOH, there is a certain amount of noise-like sound related to the passage of a bow over a string that might self-dither it enough. At any rate, record that solo violin at a nominal distance in a NC30 concert hall, and self-dithering is a slam dunk. |
#115
Posted to rec.audio.pro
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High-end audio
"hank alrich" wrote in message ... Peter Larsen wrote: wrote: I'll make you the same offer I make everyone else: Please create your own example file showing that dither makes an audible difference for music recorded at normal levels, and post it for all to hear. Please define "showing", I may be lame-brained tonight, but I don't quite understand how to meet your requirements. What is it you ask for? I'd be more interested in hanging with someone like Dave Collins in his mastering suite and have him show me how he chooses a specific dither at the final stage of a CD mastering project to see if I can hear it in that context. Sighted evaluation, yes. Good blind test, no. |
#116
Posted to rec.audio.pro
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High-end audio
"Scott Dorsey" wrote in message ... Mxsmanic wrote: Scott Dorsey writes: I suggest you actually try this instead of just pretending to have done so. I actually tried it. Take an uncompressed file like a .wav, put it into a video container file and upload it. What comes back won't be anything like what you sent up. I was comparing the files he sent me, which he said were the original and the YouTube versions. If they were truly what he told me they were, there was no significant degradation in the YouTube audio. No. Try it yourself, with your own file. Start out with uncompressed clean audio so you know where you're beginning. Then when you get it back, subtract it from the original. It's going to take you some time to get the two lined up perfectly so they subtract at all, but you'll find that at no point do they subtract reasonably well. The difference file is quite enlightening to listen to. What's interesting is that the same thing is apt to happen to the video as well as to the audio. Youtube uses perceptual encoding for both, so for they audio they basically throw away anything that the algorithm thinks won't be audible. What gets thrown away is between 70% and 90% of the actual data stream going up if you're sending up uncompressed audio. That's how all lossy compression for audio and video generally works these days. Otherwise YouTube would not be able to compressed video by nearly 500 to 1 with so few artifacts. Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. Not all lossy compression is the same. 128 kb MP3s have a fairly elevated noise floor that is an artifact of the lossy compression. 320K MP3s generally have noise due to the lossy compression that is well below the noise levels seen in even program material with exceptionally low noise floors. That's not to say that 320K MP3s are always sonically perfect, but they fall on their faces very rarely, and over different issues. |
#117
Posted to rec.audio.pro
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High-end audio
"William Sommerwerck" wrote in message ... "Arny Krueger" wrote in message ... "William Sommerwerck" wrote in message ... The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. Dither is simply noise that is added to the signal, so it is there ready when the quantization occurs. It matters not a jot how long before quantization the noise got there. If it is added at the microphone, it is exactly the same as if it was added a nanosecond before quantization. All that matters is that it is a signal free from correlation. Noise, in other words. Forgive me, Mr Pearce, but that has nothing to do with what I said. Please read what I wrote. William, this is one of the most irrational things I've read lately. Mr. Pierces comment exactly addresses your question. IT DOES NOT. It ignores my question, COMPLETELY. You're just too mentally knackered to perceive it! No, Arny, you are NOT reading what I wrote! READ IT! The issue is whether the noise already in a signal -- regardless of level -- automatically dithers it. I don't believe it does. I would like to see an explanation that goes beyond hand-waving. What part of "regardless of level" don't you understand? Asked and answered, and example of defining the desired hole given. |
#118
Posted to rec.audio.pro
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High-end audio
Arny Krueger wrote:
Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. Not all lossy compression is the same. 128 kb MP3s have a fairly elevated noise floor that is an artifact of the lossy compression. 320K MP3s generally have noise due to the lossy compression that is well below the noise levels seen in even program material with exceptionally low noise floors. That's not to say that 320K MP3s are always sonically perfect, but they fall on their faces very rarely, and over different issues. True enough. Sadly, though, YouTube's lossy compression is pretty bad by any standards, and it also interacts badly with some other lossy compression systems if you send up pre-encoded tracks. I recommend the test previously described to demonstrate this. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#119
Posted to rec.audio.pro
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High-end audio
Arny Krueger wrote:
"hank alrich" wrote in message ... Peter Larsen wrote: wrote: I'll make you the same offer I make everyone else: Please create your own example file showing that dither makes an audible difference for music recorded at normal levels, and post it for all to hear. Please define "showing", I may be lame-brained tonight, but I don't quite understand how to meet your requirements. What is it you ask for? I'd be more interested in hanging with someone like Dave Collins in his mastering suite and have him show me how he chooses a specific dither at the final stage of a CD mastering project to see if I can hear it in that context. Sighted evaluation, yes. Good blind test, no. Yep, for the most part. I don't have to be paying attention for this kind of thing. In fact, when I work with Jerry Tubb we have a brief conversation about the project, my goals for it, if I know anything he should know before he starts working. He'll then determine how much headroom is available, and we may talk about that. Then I sit down at the back of the room and go to work on other things. Album credits, email, rec.audio.pro g, etc. I don't pay any attention to what he's doing unless/until I hear something that grabs my attention. Then I'll ask him a question. On very rare ocassions I'll hear something that nobody else in the room has noticed, reminding me that beyond the commonalities of physiology and physics we are different in many ways. In particular I have learned that I am quite sensitive to low level short duration noises. If I try to pay close attention from the gitgo I don't hear the details as well. I wind up focused on the mix instead of the sound itself. We're not there for me to be deciding it's time to change the mix. g -- shut up and play your guitar * http://hankalrich.com/ http://www.youtube.com/walkinaymusic http://www.sonicbids.com/HankandShaidri |
#120
Posted to rec.audio.pro
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High-end audio
"Scott Dorsey" wrote in message ... Arny Krueger wrote: Yes. That's the problem, lossy compression degrading the audio quality. You don't get something for nothing. Not all lossy compression is the same. 128 kb MP3s have a fairly elevated noise floor that is an artifact of the lossy compression. 320K MP3s generally have noise due to the lossy compression that is well below the noise levels seen in even program material with exceptionally low noise floors. That's not to say that 320K MP3s are always sonically perfect, but they fall on their faces very rarely, and over different issues. True enough. Sadly, though, YouTube's lossy compression is pretty bad by any standards, and it also interacts badly with some other lossy compression systems if you send up pre-encoded tracks. Yes, the audible loss one finds on YouTube files can really be sonically daunting. I always smile when someone tries to illustrate why I need some subtle sonic improvement with a Youtube video. ;-) I recommend the test previously described to demonstrate this. If you got the equipment in front of you and particularly if you have to make your own test media, .wav or other lossless (e.g. FLAC) files are the way to go. |
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