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#201
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Advantage of tape over MD?
Dick Pierce wrote: This statement, all by itself, shows the patent absurdity of "Lords" position, illustrating how technically inept he is. The terms "average RMS" and "maximum RMS" are meaningless: RMS is RMS. There is but a single RMS figure for a sognal computed over the interval. There is no "maximum" or "avergae" RMS. Not quite true. In CEP, for example, one can specify a window of evaluation and it will report the maximum RMS value over that width window (50 ms is the default) within the file. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#202
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Advantage of tape over MD?
"Bob Cain" wrote in message
Dick Pierce wrote: This statement, all by itself, shows the patent absurdity of "Lords" position, illustrating how technically inept he is. The terms "average RMS" and "maximum RMS" are meaningless: RMS is RMS. There is but a single RMS figure for a sognal computed over the interval. There is no "maximum" or "avergae" RMS. Not quite true. In CEP, for example, one can specify a window of evaluation and it will report the maximum RMS value over that width window (50 ms is the default) within the file. I see no conflict here. Piece said that there is but a single RMS figure for a signal computed over the interval. What CEP does is chop the user's interval into smaller intervals the size of the window, and then report RMS values for selected windows. I don't get why people are talking about RMS values in the context of CEP and normalization when it is so clear that CEP bases normalization on the largest magnitude any single sample in the user's interval. |
#203
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Advantage of tape over MD?
Bob Cain wrote in message ...
Dick Pierce wrote: This statement, all by itself, shows the patent absurdity of "Lords" position, illustrating how technically inept he is. The terms "average RMS" and "maximum RMS" are meaningless: RMS is RMS. There is but a single RMS figure for a sognal computed over the interval. There is no "maximum" or "avergae" RMS. Not quite true. In CEP, for example, one can specify a window of evaluation and it will report the maximum RMS value over that width window (50 ms is the default) within the file. No doubt, and that is entirely consistent with my statement: "There is but one RMS figure for the signal computed over the interval." Please note the phrase "over the interval," congruent with the width of the evaluation window. Regardless of whether you use the qualifier "window width" or "over the interval," there is one and only one RMS figure for the data. If Lord HuffenPuffer is making statements about "average RMS" and "maximum RMS," he is either utterly clueless as to the principles involved or is being a deliberately destructuve troll. |
#204
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Advantage of tape over MD?
Arny Krueger wrote: I see no conflict here. Piece said that there is but a single RMS figure for a signal computed over the interval. What CEP does is chop the user's interval into smaller intervals the size of the window, and then report RMS values for selected windows. Not sure what you mean by "interval" here. The Analyze funtion runs a sliding window of a specifiable width over the selected region and samples the RMS value within the sliding window to report it's "Maximum" and "Minimum" values. I don't get why people are talking about RMS values in the context of CEP and normalization when it is so clear that CEP bases normalization on the largest magnitude any single sample in the user's interval. Unless you use it's "Group Normalize" function accessable in 2.x from the multitrack view. The "Analyze" function available in track view has always had "Average", "Maximum", "Minimum", and "Total" RMS values in its report. I'm not sure the distinction between "Average" and "Total". Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#205
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Advantage of tape over MD?
"Bob Cain" wrote ...
Dick, have you actually used CEP's "Waveform Statistics" function (sorry, Arny, I called it "Analyze" in my response to you)? What you say is not correct. The function runs a window of a specifiable width over the overall region that is selected and remembers the maximum and minimum values seen in that window. There is a separate value reported which is the single value that you refer to which applies to the whole selected region. 50mS is the default interval. I wonder if the average (RMS) of all the 50mS averages is the same as the average over the entire file? |
#206
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Advantage of tape over MD?
Richard Crowley wrote: "Bob Cain" wrote ... Dick, have you actually used CEP's "Waveform Statistics" function (sorry, Arny, I called it "Analyze" in my response to you)? What you say is not correct. The function runs a window of a specifiable width over the overall region that is selected and remembers the maximum and minimum values seen in that window. There is a separate value reported which is the single value that you refer to which applies to the whole selected region. 50mS is the default interval. I wonder if the average (RMS) of all the 50mS averages is the same as the average over the entire file? This has puzzled me. "Average" and "Total" are usually pretty close but they do differ. I think, but am not sure, that "Average" is just the average of all the windows while "Total" is what we usually measure as the RMS level of a region. I'm not really sure how to interpret the difference. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#207
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Advantage of tape over MD?
"Bob Cain" wrote in message
Arny Krueger wrote: I see no conflict here. Pierce said that there is but a single RMS figure for a signal computed over the interval. What CEP does is chop the user's interval into smaller intervals the size of the window, and then report RMS values for selected windows. Not sure what you mean by "interval" here. The Analyze function runs a sliding window of a specifiable width over the selected region and samples the RMS value within the sliding window to report it's "Maximum" and "Minimum" values. The RMS measurement interval is the width of the window, right? I don't get why people are talking about RMS values in the context of CEP and normalization when it is so clear that CEP bases normalization on the largest magnitude of any single sample in the user's interval. Unless you use it's "Group Normalize" function accessible in 2.x from the multitrack view. The Help file seems to say that Group Normalize still bases its operation on peak values. The "Analyze" function available in track view has always had "Average", "Maximum", "Minimum", and "Total" RMS values in its report. I'm not sure the distinction between "Average" and "Total". I can't see where the help file sheds any light on that question. My understandings suggest that they should be the same, but they clearly aren't often the same with real world signals. BTW, thanks for the stimulus to read the docs, even if not all my questions were answered. |
#208
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Advantage of tape over MD?
Bob Cain wrote in
: Dick, have you actually used CEP's "Waveform Statistics" function (sorry, Arny, I called it "Analyze" in my response to you)? What you say is not correct. The function runs a window of a specifiable width over the overall region that is selected and remembers the maximum and minimum values seen in that window. There is a separate value reported which is the single value that you refer to which applies to the whole selected region. So the program computes RMS within a window, shifts the window (with or without overlap) and repeats. So each interval has one unique RMS value, no? This would still agree with what Mr. Pierce is saying. Tim |
#209
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Advantage of tape over MD?
On 6 Jul 2003 14:21:29 -0700, Dick Pierce wrote:
If Lord HuffenPuffer is making statements about "average RMS" and "maximum RMS," he is either utterly clueless as to the principles involved or is being a deliberately destructuve troll. Which is more or less where we came in with the arse whipping he gave MFSL ;-) |
#210
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Advantage of tape over MD?
Browntimdc wrote: Bob Cain wrote in : Dick, have you actually used CEP's "Waveform Statistics" function (sorry, Arny, I called it "Analyze" in my response to you)? What you say is not correct. The function runs a window of a specifiable width over the overall region that is selected and remembers the maximum and minimum values seen in that window. There is a separate value reported which is the single value that you refer to which applies to the whole selected region. So the program computes RMS within a window, shifts the window (with or without overlap) and repeats. So each interval has one unique RMS value, no? This would still agree with what Mr. Pierce is saying. Perhaps I misunderstood but my interpretation of what he said was that the idea of a minimum and maximum RMS value have no meaning. I'm just saying that it can be given a meaning by assigning an RMS value to each point that is the the RMS value of a window centered on that point. In that case minima and maxima can be discussed and have intuitive as well as utility value. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#211
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Advantage of tape over MD?
Martin Tillman wrote:
CEP analyses a file by looking at specific time intervals (default 50ms) and calculating the RMS power for that interval. Someone might find that useful. It then reports the max and min values it found - meaning the max and min for the 50ms intervals. If you want to normalise your file based on the value of 50ms of it, please feel free. Then it takes all the RMS values for the file and averages them. This gives the average of all the values (just to be clear...). It also reports the total RMS power of the file, which is not the same as the average of all the values. Normalize uses similar procedures and reports back its own Maximum RMS level as the "level" of the song - and *that's* the level that it uses as a guide for adjusting loudnesses, not the Average RMS level as everyone has been assuming to be the case. Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#212
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Advantage of tape over MD?
In rec.audio.tech Lord Hasenpfeffer wrote:
: and the range is right there waiting for you to use it - I say, by all : means, do. But that is done by saturating the original recordings, long before mastering. All the normalizing in the world is not going to increase the dynamic range of the recording. Scott |
#213
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Advantage of tape over MD?
sgordon wrote:
In rec.audio.tech Lord Hasenpfeffer wrote: : and the range is right there waiting for you to use it - I say, by all : means, do. But that is done by saturating the original recordings, long before mastering. All the normalizing in the world is not going to increase the dynamic range of the recording. You are correct. Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#214
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Advantage of tape over MD?
"Lord Hasenpfeffer" wrote in message ... Martin Tillman wrote: CEP analyses a file by looking at specific time intervals (default 50ms) and calculating the RMS power for that interval. Someone might find that useful. It then reports the max and min values it found - meaning the max and min for the 50ms intervals. If you want to normalise your file based on the value of 50ms of it, please feel free. Then it takes all the RMS values for the file and averages them. This gives the average of all the values (just to be clear...). It also reports the total RMS power of the file, which is not the same as the average of all the values. Normalize uses similar procedures and reports back its own Maximum RMS level as the "level" of the song - and *that's* the level that it uses as a guide for adjusting loudnesses, not the Average RMS level as everyone has been assuming to be the case. The CEP normalize function is based on peak levels - the sample in the data being normalized with the largest magnitude. |
#215
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Advantage of tape over MD?
Arny Krueger wrote: The CEP normalize function is based on peak levels - the sample in the data being normalized with the largest magnitude. Arny, CEP 2.x has a "Group Normalize" function available from the multitrack view which works on multiple files and utilizes RMS levels. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#216
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Advantage of tape over MD?
Arny Krueger wrote:
As far as I can tell this is irrelevant to the discussion at hand which relates to 2-channel MP3s. I see it as just one of many red herrings that were dragged in, resulting in a complex and inconclusive discussion of a fairly simple problem. And MiniDiscs... Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#217
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Advantage of tape over MD?
Arny Krueger wrote: "Bob Cain" wrote in message ... Arny Krueger wrote: The CEP normalize function is based on peak levels - the sample in the data being normalized with the largest magnitude. Arny, CEP 2.x has a "Group Normalize" function available from the multitrack view which works on multiple files and utilizes RMS levels. As far as I can tell this is irrelevant to the discussion at hand which relates to 2-channel MP3s. I see it as just one of many red herrings that were dragged in, resulting in a complex and inconclusive discussion of a fairly simple problem. Perhaps the thread is too long for your limited attention span, and perhaps it has wandered about some, but initially it was about normalizing groups of CD tracks prior to making MP3's from them. The question of basing that on RMS levels has been relevant from the beginning and I'm pointing out how CEP can do that (which you said it couldn't.) Bad day, Arny? Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#218
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Advantage of tape over MD?
"Paul Dormer" wrote in message
Normalizing a bunch of tracks together isn't a bad idea, but I would discourage newbies from normalizing individual tracks - software just doesn't understand the difference between ballads and trash metal.. IOW, normalizing is a poor choice as a means to match perceived loudness. Matching perceived levels based on RMS values is generally more effective than using peak levels. However, RMS measurements don't consider spectral balance, which is very important to perceptions of perceived loudness. |
#219
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Advantage of tape over MD?
Could I enter this discussion, or is private?
Today, rock and pop music is largely electronic and composed in the mixing room. It's also compressed to the point of near death. How one handles this is largely a matter of taste. Since it's already been clipped, smashed and otherwise manhandled almost any method of volume adjustment will work just fino. In the case of classical music, I imagine a perfect recording is the starting point--no compression, clipping, and the level of the original is adjusted so that it has a full dynamic range, but as little as possible wasted at the peak. This works well on the original, but makes for some awkwardness in the release version. It's entirely possible that a full symphony orchestra will have more than one peak level: The apparent maximum output, and also the absolute instantaneous peak that could easily run 10's of db above the apparent maximum level, but only for a few milliseconds. The human ear/brain is highly nonlinear. The shorter a peak is, the less apt the brain is to give it full value. So, the solution is to compress these very short peaks so that there's room left to bring up the apparent level to where it sounds much the same as other recordings. A very good article on this subject is entitled "How can the headroom of digital recordings be used optimally?" Written by Manfred Krause and Holger Petersen, it's in the Journal of the Audio Engineering Society, Vol 38, No.11, dated November 1990. Norm Strong "Bob Cain" wrote in message ... Arny Krueger wrote: "Bob Cain" wrote in message ... Arny Krueger wrote: The CEP normalize function is based on peak levels - the sample in the data being normalized with the largest magnitude. Arny, CEP 2.x has a "Group Normalize" function available from the multitrack view which works on multiple files and utilizes RMS levels. As far as I can tell this is irrelevant to the discussion at hand which relates to 2-channel MP3s. I see it as just one of many red herrings that were dragged in, resulting in a complex and inconclusive discussion of a fairly simple problem. Perhaps the thread is too long for your limited attention span, and perhaps it has wandered about some, but initially it was about normalizing groups of CD tracks prior to making MP3's from them. The question of basing that on RMS levels has been relevant from the beginning and I'm pointing out how CEP can do that (which you said it couldn't.) Bad day, Arny? Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#220
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Advantage of tape over MD?
Paul Dormer wrote:
Who gives a ****? Both formats are history. Says you. Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#221
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Advantage of tape over MD?
Paul Dormer wrote:
Normalizing a bunch of tracks together isn't a bad idea, but I would discourage newbies from normalizing individual tracks - software just doesn't understand the difference between ballads and trash metal.. This is an excellent point. I remember when I got to my John Denver CDs and Normalized them in my usual way. "Take Me Home, Country Roads" sounded painfully wrong to my ears after that. Needless to say, I redid those files at a much more conservative level. Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#222
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Advantage of tape over MD?
On Fri, 11 Jul 2003 23:19:42 -0500, Lord Hasenpfeffer wrote:
Paul Dormer wrote: Normalizing a bunch of tracks together isn't a bad idea, but I would discourage newbies from normalizing individual tracks - software just doesn't understand the difference between ballads and trash metal.. This is an excellent point. I remember when I got to my John Denver CDs and Normalized them in my usual way. "Take Me Home, Country Roads" sounded painfully wrong to my ears after that. Needless to say, I redid those files at a much more conservative level. Did you set your normalize value to 0 ? That's where Denver sounds best. You're welcome. |
#223
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Advantage of tape over MD?
George W. wrote:
Did you set your normalize value to 0 ? That's where Denver sounds best. You're welcome. Are you implying that John Denver's music sucks big green donkey dongs? Myke -- -================================- Windows...It's rebootylicious!!! -================================- |
#224
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Advantage of tape over MD?
Lord Hasenpfeffer wrote: Bob Cain wrote: Perhaps the thread is too long for your limited attention span, and perhaps it has wandered about some, but initially it was about normalizing groups of CD tracks prior to making MP3's from them. Actually, that's not entirely true - as I also do a lot of MiniDisc recording which is also lossy although to a much lesser extent than with common MP3s. That's why the thread in the other NG says "(With Lossy)" instead of "(With MP3)". That's right, it was for ATRAC rather than MP3. Chalk it up to my limited attention span. :-) Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#225
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Advantage of tape over MD?
In article ,
Ken Bouchard wrote: OK, since Nyquist was mentioned, I'll go ahead and ask this: According to Nyquists theorem, a waveform only has to be sampled at a rate TWICE it's highest frequency, right? Wrong, it's more than twice. Hence, we sample most audio waves (for CD anyway) at 44.1 KHZ because thats about TWICE the highest frequency we humans can hear, right? OK, let's take a waveform that's got a sound in it with a frequency way up there like at 22 KHZ. (I've got REAL good hearing:-) How can that high frequency be faithfully reproduced if it's only being sampled a couple times? Because if your waveform is at 22 kHz, any deviations from that 22 kHz sine wave MUST be at multiples of 22 kHz, and anything at 22.05 kHz and above MUST be eliminated by the prerequisite filtering any sampling system must have. Let's look at it more fundamentally. A 44.1 kHz system MUST have its bandwidth limited to less than 22.05 kHz. This is simply the correlary of saying that you must sample at more than twice a waveform's frequency. If the bandwidth is limited to 22.05 kHz, only one kind of 22 kHz waveform can possibly exist: a 22 kHz sine wave. You can't have a 22 kHz square wave or triangle wave or perfect tone burst because ALL of those waveforms have components outside of the 22.05 kHz bandwidth that this system has. Given that, the number of points needed to PERFECTLY represent a 22 kHz SINE waveform with PERFECT fidelity is only slightly more tha 2 per cycle. Only one sine wave can pass through those points. Only one, and that's the original waveform. That's essentially the non-methematical statement of the mathematical proof of the sampling theorem. Now, you are undoubtedly still wondering how this can be. If you take these two points and "connect the dots," you don't get a 22 kHz sine wave. You get something else entirely. Well, if we were to look at the spectrum of the signal represented by the "connect-the-dot" waveform, we'd find that it would consist of since components at 22 kHz and at many other frequencies, all above 22.05 kHz. For example, you'd have a component at 22.1 kHz, one at 44 kHz, one at 44.2 kHz and so on and so forth. But, all those extra components aren't permitted, since they all violate the Nyquist criteria. So, as soonas we get rid of them all, all but the 22 kHz component poof! we have our 22 kHz waveform back again, just as it originally was. So filtering is needed in two places: first, when we sample, because Nyquist says we cannot sample wavforms equal to or greater than the sampling frquency: That;s at the original A/D stage. Second, when we convert back to the analog domain: the extra components that result from the "connect-the-dots" or "stair case" (or whatever representation) are outside the Nyquist band and also must be eliminated. It works just fine boith in theory and in practice. -- | Dick Pierce | | Professional Audio Development | | 1-781/826-4953 Voice and FAX | | | |
#226
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Advantage of tape over MD?
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#227
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Advantage of tape over MD?
"A E" wrote in message And all perfectly irrelevant because you will never hear that. And is the same in any band-limited scenario ( not just digital) , as in recording with real-world micophones, onto reel tapes, etc. geoff |