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#1
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Class D power amplifier---what about class-D CD?
Just wondering...
If the music producer can record music as PWM (pulse width modulation) signal direct onto CD. Than a "class-D" CD player doesn't need a Digital-Analog converter. The PWM signal can be feed direct to a class D power amplifier. This can save a lot of "signal conversion'" |
#2
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 17:40:55 +0800, "New_idea"
wrote: Just wondering... If the music producer can record music as PWM (pulse width modulation) signal direct onto CD. Than a "class-D" CD player doesn't need a Digital-Analog converter. The PWM signal can be feed direct to a class D power amplifier. This can save a lot of "signal conversion'" One word. Jitter. d |
#3
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Class D power amplifier---what about class-D CD?
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#4
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
There are practical issues involved. One is sampling rate. Another is the
way "Class D" is implemented in a given amplifier. There's also the issue of whether (here we go!) the PWM should be analog or digital. As another poster pointed out, jitter would be a problem, much more for analog than digital -- not to mention the difficulty of exactly controlling the pulse width in a polycarbonate pit. It isn't an inherently bad idea. It's technically feasible, just not commercially practical at this time. |
#5
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 04:38:40 -0700, "William Sommerwerck"
wrote: There are practical issues involved. One is sampling rate. Another is the way "Class D" is implemented in a given amplifier. There's also the issue of whether (here we go!) the PWM should be analog or digital. As another poster pointed out, jitter would be a problem, much more for analog than digital -- not to mention the difficulty of exactly controlling the pulse width in a polycarbonate pit. It isn't an inherently bad idea. It's technically feasible, just not commercially practical at this time. When you say digital, do you mean store the data as a number, as is done now, and feed it to a DAC, the output of which is a pulse width rather than a voltage? If so, that could be done with the CDs we have right now. d |
#6
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
When you say digital, do you mean store the data as a number,
as is done now, and feed it to a DAC, the output of which is a pulse width rather than a voltage? If so, that could be done with the CDs we have right now. Here we go... When I say "digital", I mean "quantized" -- there is only a finite number of possible pulse widths. This is doable right now, and in fact was done 30 years ago, with the original LaserDisks, which used a form of analog pulse-width modulation. |
#7
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 05:11:34 -0700, "William Sommerwerck"
wrote: When you say digital, do you mean store the data as a number, as is done now, and feed it to a DAC, the output of which is a pulse width rather than a voltage? If so, that could be done with the CDs we have right now. Here we go... When I say "digital", I mean "quantized" -- there is only a finite number of possible pulse widths. This is doable right now, and in fact was done 30 years ago, with the original LaserDisks, which used a form of analog pulse-width modulation. OK, I get it. But why would the possible number of pulse widths be finite (apart from quantum effects of course)? You can theoretically make a pit any arbitrary length. Of course you would instantly be at the mercy of scratches and dirt. Error correction would be a thing of the past. d |
#8
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
When you say digital, do you mean store the data as a number,
as is done now, and feed it to a DAC, the output of which is a pulse width rather than a voltage? If so, that could be done with the CDs we have right now. When I say "digital", I mean "quantized" -- there is only a finite number of possible pulse widths. This is doable right now, and in fact was done 30 years ago, with the original LaserDisks, which used a form of analog pulse-width modulation. OK, I get it. But why would the possible number of pulse widths be finite (apart from quantum effects of course)? You can theoretically make a pit any arbitrary length. Of course you would instantly be at the mercy of scratches and dirt. Error correction would be a thing of the past. I feel like Peewee Herman going "Aaaaaahhh!" Yes, the pit _can_ be of any arbitrary length. But if we quantize the length, then we have a digital system. If the width falls within a particular range, then we know -- with almost perfect certainty -- what _number_ it represents. As you point out, this is not possible in an analog system. |
#9
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 05:29:55 -0700, "William Sommerwerck"
wrote: When you say digital, do you mean store the data as a number, as is done now, and feed it to a DAC, the output of which is a pulse width rather than a voltage? If so, that could be done with the CDs we have right now. When I say "digital", I mean "quantized" -- there is only a finite number of possible pulse widths. This is doable right now, and in fact was done 30 years ago, with the original LaserDisks, which used a form of analog pulse-width modulation. OK, I get it. But why would the possible number of pulse widths be finite (apart from quantum effects of course)? You can theoretically make a pit any arbitrary length. Of course you would instantly be at the mercy of scratches and dirt. Error correction would be a thing of the past. I feel like Peewee Herman going "Aaaaaahhh!" Yes, the pit _can_ be of any arbitrary length. But if we quantize the length, then we have a digital system. If the width falls within a particular range, then we know -- with almost perfect certainty -- what _number_ it represents. As you point out, this is not possible in an analog system. Why would you want it to represent a number? This is a bit like reading a voltage with an A/D, then instantly converting it back to a voltage (with steps) to record it onto e.g. vinyl. The intervening digital stage has been pointless. d |
#10
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
"New_idea" wrote in message
Just wondering... If the music producer can record music as PWM (pulse width modulation) signal direct onto CD. What's wrong with PCM? Than a "class-D" CD player doesn't need a Digital-Analog converter. Why worry about solved problems? DACs are now cheap and good. The PWM signal can be feed direct to a class D power amplifier. Providing it used pure PWM, which is not a given. This can save a lot of "signal conversion'" Not a serious problem right now. Here's a question - how will you implement tone and volume controls? |
#11
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 08 Oct 2009 08:43:18 -0400, Arny Krueger wrote:
Here's a question - how will you implement tone and volume controls? That's easy - just change the supply voltage to the power output stage. (how to do that efficiently is left as an exercise for the reader....) -- Anahata ==//== 01638 720444 http://www.treewind.co.uk ==//== http://www.myspace.com/maryanahata |
#12
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 08 Oct 2009 08:44:42 -0500, anahata wrote:
That's easy - just change the supply voltage to the power output stage. (how to do that efficiently is left as an exercise for the reader....) I meant to say "volume's easy...." of course. -- Anahata |
#13
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
"anahata" wrote in message
o.uk On Thu, 08 Oct 2009 08:43:18 -0400, Arny Krueger wrote: Here's a question - how will you implement tone and volume controls? That's easy - just change the supply voltage to the power output stage. (how to do that efficiently is left as an exercise for the reader....) Even for just volume controls, that methodology gets dicy for high levels of attenuation. |
#14
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
William Sommerwerck wrote:
There are practical issues involved. One is sampling rate. Another is the way "Class D" is implemented in a given amplifier. There's also the issue of whether (here we go!) the PWM should be analog or digital. As another poster pointed out, jitter would be a problem, much more for analog than digital -- not to mention the difficulty of exactly controlling the pulse width in a polycarbonate pit. It isn't an inherently bad idea. It's technically feasible, just not commercially practical at this time. Not clear that it is inherently a good idea, either. One reason it isn't commercially practical is that it gives up all the benefits of digital encoding and transmission (like error detection and correction, etc.). You end up with a much LESS robust system that doesn't have any upside potential. An amusing thought problem, but no apparent practial benefits. As Mr. Dorsey has observed here before, there isn't really any true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. |
#15
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
Why would you want it to represent a number? This is a bit like
reading a voltage with an A/D, then instantly converting it back to a voltage (with steps) to record it onto e.g. vinyl. The intervening digital stage has been pointless. Because if it represents a specific number, then it's much easier to read its intended value -- because you have a priori information about the nature of the signal. This is one of the ways digital transmission reduces the effects of noise (both amplitude and phase). |
#16
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 07:15:47 -0700, "William Sommerwerck"
wrote: Why would you want it to represent a number? This is a bit like reading a voltage with an A/D, then instantly converting it back to a voltage (with steps) to record it onto e.g. vinyl. The intervening digital stage has been pointless. Because if it represents a specific number, then it's much easier to read its intended value -- because you have a priori information about the nature of the signal. This is one of the ways digital transmission reduces the effects of noise (both amplitude and phase). You need to go and have a bit of a think about this. The number is directly proportional to the pit length. So whether the pit length represents a number, which in turn represents a voltage, or represents the voltage directly, the same length errors have the same final voltage effect. d |
#17
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
You need to go and have a bit of a think about this. The number
is directly proportional to the pit length. So whether the pit length represents a number, which in turn represents a voltage, or represents the voltage directly, the same length errors have the same final voltage effect. Not if the length is quantized. It can vary (within limits) and still be correctly read. This is not true of analog. |
#18
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
As Mr. Dorsey has observed here before, there isn't really any
true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. |
#19
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 08:04:57 -0700, "William Sommerwerck"
wrote: You need to go and have a bit of a think about this. The number is directly proportional to the pit length. So whether the pit length represents a number, which in turn represents a voltage, or represents the voltage directly, the same length errors have the same final voltage effect. Not if the length is quantized. It can vary (within limits) and still be correctly read. This is not true of analog. For goodness sake - how are you not getting this? If the error in length is less than your quantization step, then it simply isn't an error. If it is a much larger error (which is far more likely) then it doesn't matter whether there is quantization or not - the result is the same. The reason digital works is because you store the numbers, not some variable quantity that represents their magnitude. d |
#20
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Class D power amplifier---what about class-D CD?
For goodness sake - how are you not getting this? If the error in
length is less than your quantization step, then it simply isn't an error. Correct. If it is a much larger error (which is far more likely) then it doesn't matter whether there is quantization or not - the result is the same. If that occurs, it's because the system is poorly designed. A "good" digital system does not have large numbers of errors that exceed the bounds that would prevent correct reading. The reason digital works is because you store the numbers, not some variable quantity that represents their magnitude. You need to think this through. Most people -- including those with college degrees -- just don't understand that any quantization of sample amplitude is digitization of the signal. |
#21
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 08:38:57 -0700, "William Sommerwerck"
wrote: For goodness sake - how are you not getting this? If the error in length is less than your quantization step, then it simply isn't an error. Correct. If it is a much larger error (which is far more likely) then it doesn't matter whether there is quantization or not - the result is the same. If that occurs, it's because the system is poorly designed. A "good" digital system does not have large numbers of errors that exceed the bounds that would prevent correct reading. No, it is because there is dust, or the disc has got scratched, or it has been left out in the sun. The reason digital works is because you store the numbers, not some variable quantity that represents their magnitude. You need to think this through. Most people -- including those with college degrees -- just don't understand that any quantization of sample amplitude is digitization of the signal. No, digitization is representing those quantized levels by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. I have an old fuzz box for a guitar. What comes out of it is a square wave - very coarse quantization in fact. But it isn't digital. d |
#22
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
"William Sommerwerck" wrote...
As Mr. Dorsey has observed here before, there isn't really any true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. |
#23
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
No, digitization is representing those quantized levels by numbers
(these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. |
#24
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
As Mr. Dorsey has observed here before, there isn't really any
true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. What, to your ears, is the subjective effect? |
#25
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 11:17:31 -0700, "William Sommerwerck"
wrote: No, digitization is representing those quantized levels by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Absolutely so. Think about what sort of signal you would feed into a digital to analogue converter. It would not be a quantized waveform now, would it? It would be a string of ones and zeroes - that is a digital signal. d |
#26
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Class D power amplifier---what about class-D CD?
No, digitization is representing those quantized levels by numbers
(these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Absolutely so. Think about what sort of signal you would feed into a digital to analogue converter. It would not be a quantized waveform now, would it? It would be a string of ones and zeroes -- that is a digital signal. I got into a long argument about this a year ago, and I'm not going to repeat it. I know it's insufferably rude to say so, but I am absolutely right about this, and anyone who disagrees with the basic principle being stated, is wrong. Mr. Pearce, sit down for a while and think about how one distinguishes information from noise. When you have a better understanding (you might want to browse a book on information theory), you'll go "Aha! That's right! I don't know why I didn't see it before." |
#27
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 12:08:21 -0700, "William Sommerwerck"
wrote: No, digitization is representing those quantized levels by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Absolutely so. Think about what sort of signal you would feed into a digital to analogue converter. It would not be a quantized waveform now, would it? It would be a string of ones and zeroes -- that is a digital signal. I got into a long argument about this a year ago, and I'm not going to repeat it. I know it's insufferably rude to say so, but I am absolutely right about this, and anyone who disagrees with the basic principle being stated, is wrong. Mr. Pearce, sit down for a while and think about how one distinguishes information from noise. When you have a better understanding (you might want to browse a book on information theory), you'll go "Aha! That's right! I don't know why I didn't see it before." We aren't going to have an argument because I remember the last one well. You were wrong then as you are wrong now. We can leave it at that. The fact that you thought your second paragraph might shed some light is all we need to see the nature of your misunderstanding of the terms. d |
#28
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
No, digitization is representing those quantized levels by numbers
(these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Absolutely so. Think about what sort of signal you would feed into a digital to analogue converter. It would not be a quantized waveform now, would it? It would be a string of ones and zeroes -- that is a digital signal. I got into a long argument about this a year ago, and I'm not going to repeat it. I know it's insufferably rude to say so, but I am absolutely right about this, and anyone who disagrees with the basic principle being stated, is wrong. Mr. Pearce, sit down for a while and think about how one distinguishes information from noise. When you have a better understanding (you might want to browse a book on information theory), you'll go "Aha! That's right! I don't know why I didn't see it before." We aren't going to have an argument because I remember the last one well. You were wrong then as you are wrong now. We can leave it at that. The fact that you thought your second paragraph might shed some light is all we need to see the nature of your misunderstanding of the terms. Indeed, what I said is the essence of the issue. I would suggest that you speak with someone genuinely knowledgeable about information theory. We will leave it at that. |
#29
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 12:38:29 -0700, "William Sommerwerck"
wrote: No, digitization is representing those quantized levels by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Absolutely so. Think about what sort of signal you would feed into a digital to analogue converter. It would not be a quantized waveform now, would it? It would be a string of ones and zeroes -- that is a digital signal. I got into a long argument about this a year ago, and I'm not going to repeat it. I know it's insufferably rude to say so, but I am absolutely right about this, and anyone who disagrees with the basic principle being stated, is wrong. Mr. Pearce, sit down for a while and think about how one distinguishes information from noise. When you have a better understanding (you might want to browse a book on information theory), you'll go "Aha! That's right! I don't know why I didn't see it before." We aren't going to have an argument because I remember the last one well. You were wrong then as you are wrong now. We can leave it at that. The fact that you thought your second paragraph might shed some light is all we need to see the nature of your misunderstanding of the terms. Indeed, what I said is the essence of the issue. I would suggest that you speak with someone genuinely knowledgeable about information theory. We will leave it at that. I am knowledgable on information theory, thank you. I am the author of several ETSI standards for digital transmission, and have designed digital + analogue signal generators for Marconi Instruments. By your definition the audio signal that comes OUT of my CD player is digital. It simply isn't. d |
#30
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Class D power amplifier---what about class-D CD?
I am knowledgeable on information theory, thank you.
I am the author of several ETSI standards for digital transmission, and have designed digital + analogue signal generators for Marconi Instruments. If you actually did understand information theory, you would have understood what I was saying "at once" -- or you would have figured it out long ago. Hell, I buy photo magazines with article written by people who know almost nothing about what they're writing about. By your definition the audio signal that comes OUT of my CD player is digital. It simply isn't. I never said that -- at least in this discussion. Give me a call over the weekend. Perhaps a verbal explanation will clear things up. 425-235-9579 |
#31
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Class D power amplifier---what about class-D CD?
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#32
Posted to rec.audio.pro
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Class D power amplifier---what about class-D CD?
"William Sommerwerck" wrote in ...
As Mr. Dorsey has observed here before, there isn't really any true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. What, to your ears, is the subjective effect? The noise/distortion floor increases. You can do an experiment where you can take a 16-bit recording and resample to 12-bit, and 10-bit and 8-bit and hear the "hash" floor rising under the signal. Much like driving over a freshly paved macadam (blacktop, tarmac) road vs. a gravel road. They will both get you there, but one of them much more quitetly than the other. |
#33
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Class D power amplifier---what about class-D CD?
"William Sommerwerck" wrote ...
No, digitization is representing those quantized levels by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Sampling and digitization are separate and independent phenomenon. Perhaps you are unaware of CCD aka. "bucket-brigade" which is most certainly *sampling* but also most certainly ANALOG and NOT digital. In fact the higher-capacity flash memory (EEPROM) is now making use of the technique of storing two or even four different charge quanta in a single cell in order to store more than one digital bit per memory cell. |
#34
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Class D power amplifier---what about class-D CD?
"Richard Crowley" wrote in message
... "William Sommerwerck" wrote in ... As Mr. Dorsey has observed here before, there isn't really any true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. What, to your ears, is the subjective effect? The noise/distortion floor increases. You can do an experiment where you can take a 16-bit recording and resample to 12-bit, and 10-bit and 8-bit and hear the "hash" floor rising under the signal. Much like driving over a freshly paved macadam (blacktop, tarmac) road vs. a gravel road. They will both get you there, but one of them much more quitetly than the other. How do you know that these audible effects are due to quantization, and not something else? |
#35
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Class D power amplifier---what about class-D CD?
No, digitization is representing those quantized levels
by numbers (these are the digits). Quantization is just quantization, nothing more. It is a jaggy waveform. Not so. Think about the _meaning_ of digital. Sampling and digitization are separate and independent phenomena. Perhaps you are unaware of CCD aka. "bucket-brigade" which is most certainly *sampling* but also most certainly ANALOG and NOT digital. Of course. That wasn't what I was talking about. I was talking about amplitude quantization -- not temporal quantization. |
#36
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Class D power amplifier---what about class-D CD?
"William Sommerwerck"wrote ...
How do you know that these audible effects are due to quantization, and not something else? Because only quantization is changed. One equation, one unknown. |
#37
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Class D power amplifier---what about class-D CD?
On Thu, 8 Oct 2009 12:50:41 -0700, "William Sommerwerck"
wrote: I am knowledgeable on information theory, thank you. I am the author of several ETSI standards for digital transmission, and have designed digital + analogue signal generators for Marconi Instruments. If you actually did understand information theory, you would have understood what I was saying "at once" -- or you would have figured it out long ago. Hell, I buy photo magazines with article written by people who know almost nothing about what they're writing about. By your definition the audio signal that comes OUT of my CD player is digital. It simply isn't. I never said that -- at least in this discussion. You didn't have to say it, it was implicit. The signal that comes out of a CD player is quantized, therefore by your definition it is digital. d |
#38
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Class D power amplifier---what about class-D CD?
New_idea wrote:
Just wondering... If the music producer can record music as PWM (pulse width modulation) signal direct onto CD. Than a "class-D" CD player doesn't need a Digital-Analog converter. The PWM signal can be feed direct to a class D power amplifier. This can save a lot of "signal conversion'" This is how SACD works. Sony marketed it aggressively for a while, but seems to have given up on it. It has good points and bad ones, and was extensively discussed here five or six years ago when it was a hot topic. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#39
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Class D power amplifier---what about class-D CD?
As Mr. Dorsey has observed here before, there isn't really any
true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. What, to your ears, is the subjective effect? The noise/distortion floor increases. You can do an experiment where you can take a 16-bit recording and resample to 12-bit, and 10-bit and 8-bit and hear the "hash" floor rising under the signal. Much like driving over a freshly paved macadam (blacktop, tarmac) road vs. a gravel road. They will both get you there, but one of them much more quietly than the other. How do you know that these audible effects are due to quantization, and not something else? I thought I misread you, so I asked "how do you know?". Then you replied... Because only quantization is changed. One equation, one unknown. That was not the issue! See above. You said you could hear the effect of quantization in (presumably) analog media -- "mechanical and magnetic recording". Then you start talking about the audibility of quantization effects in digital recording. Non sequitur. |
#40
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Class D power amplifier---what about class-D CD?
"William Sommerwerck" wrote...
As Mr. Dorsey has observed here before, there isn't really any true analog recording. Mechanical recording is quantized by the wax or vinyl molecules, etc. and magnetic recording is quantized by the size of the magnetic monopoles, head gap, tape speed, etc. Yes, but... That's really stretching it. I can hear the effect in both mechanical and magnetic recording. What, to your ears, is the subjective effect? The noise/distortion floor increases. You can do an experiment where you can take a 16-bit recording and resample to 12-bit, and 10-bit and 8-bit and hear the "hash" floor rising under the signal. Much like driving over a freshly paved macadam (blacktop, tarmac) road vs. a gravel road. They will both get you there, but one of them much more quietly than the other. How do you know that these audible effects are due to quantization, and not something else? I thought I misread you, so I asked "how do you know?". Then you replied... Because only quantization is changed. One equation, one unknown. That was not the issue! See above. You said you could hear the effect of quantization in (presumably) analog media -- "mechanical and magnetic recording". Then you start talking about the audibility of quantization effects in digital recording. Non sequitur. Sequitur. I was attempting to describe an experiement you could conduct which would illustrate what quantization noise sounds like since you don't seem to be familiar with it. |
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