Hi,
Yeah...
Let's stop puncturing each others' equilibrium and have a coffee for a change...😉
My concern was: does this sensitivity to microphony affect the digital datastream in any way?
If it doesn't then I assume it shouldn't be audible unless it upsets something else...But what?
Cheers,😉
Yeah...
Let's stop puncturing each others' equilibrium and have a coffee for a change...😉
My concern was: does this sensitivity to microphony affect the digital datastream in any way?
If it doesn't then I assume it shouldn't be audible unless it upsets something else...But what?
Cheers,😉
Hi,
No...
But then we don't have anything solidly paranormal...yet.
Although I do have my reservations about that at times....
Cheers,😉
No...
But then we don't have anything solidly paranormal...yet.
Although I do have my reservations about that at times....
Cheers,😉
Well id does not affect the digital bit stream but it would have an effect on the d/a conversion process because of an unstable clock. The bit content is perfect on the input pin of the d/a chip (not counting eventual eroor correction in the read process of the disc)
/
/
TNT said:
This is why I think people do hear a diff. with shakti but it is not it's state funtion - beeing hevy.
In a shakti test I would like to do it should be attached to wires hanging from the roof 1 mm above the targeted equipment. That is <near>, no?
/
Frank,
You can't be serious asking this question. Maybe you should brush-up on jitter and DACs.
regards
serengetiplains said:
"Cryogenic treatment doesn't change the frequency of that resonance, it just changes its Q [damping]," and "it is possible that you get a network of fine cracks in such items...."
I understand that one can damp an object's resonance by reducing it's rigidity. A network of fine cracks possibly would do that for a CD. HooHa!
I have no idea if that's how the cryogenic treatment damped the CDs' resonance. But I rather doubt it.
Cds are made of polycarbonate which appears in some rather low temperature applications, as, for instance, this cryogenic grinding mill:
http://www.reflexusa.com/cryogwigmil.html
Polycarbonate is one of the materials of choice for cryogenic equipment, as a cursory Google search would show.
The rabid PC overclockers get their machines to operate at extremely low temperatures using liquid nitrogen as the refrigerant and it would seem as long as the descent to low temperature is gradual the various parts survive without damage.
CDs are made from polycarbonate slugs which are heated to a high desicatng temperature before being pressed and the aluminum layer preciptated on and the back then laquered. There is no reason to think that a CD would take any particular damage from very low temperatures providing they are brought to them gradually.
Thus far I haven't found any report about cryogenic treatment changing the structure of polycarbonate except from people who treat CDs that way.
However, polycarbonate maybe annealed in the same manner as a metal.
http://www.rmplastics.net/polycarb.htm
I suspect that since CDs are not annealed after manufacture and that since Meitner reports their resonance is damped by cryogenic treatment that some process analogous to annealing takes place making the disc less rigid.
But it isn't necessary to know what the process is since Meitner's claim is very easy to check..
Konnichiwa,
CD-Rom uses a different fundamental file structure. The CD Rom file structure writes appx. 20% of the Data with REDUNDANT information that aids arror recovery. There is no such mechanism for Red-Book Audio CD. The Error correction is extremely basic. This was seen at the time as sufficient, as interpolation and other concealment methodes INCORPORATED into the whole error correction would make any unreadable sections "inaudible".
CD Roms remain readable with much worse damage to the Disk than Audio CD's. Try it one day.
Sayonara
fdegrove said:
CD-Rom uses a different fundamental file structure. The CD Rom file structure writes appx. 20% of the Data with REDUNDANT information that aids arror recovery. There is no such mechanism for Red-Book Audio CD. The Error correction is extremely basic. This was seen at the time as sufficient, as interpolation and other concealment methodes INCORPORATED into the whole error correction would make any unreadable sections "inaudible".
fdegrove said:
CD Roms remain readable with much worse damage to the Disk than Audio CD's. Try it one day.
Sayonara
So many so sure!
The signal from a CD mechanism is a high frequency analogue signal not a digital one. There's plenty of opportunity for it to be affected by a host of things, not least vibration, be that directly, or via secondary effects.
It certainly exists in electronics, so it's not impossible. Somewhere I have an LT data sheet (IIRC) on voltage references that actually has 'scope traces of the effect on output noise of tapping a capacitor with a pencil.
My guess is this is such a hard leap for you, because you obviously haven't looked at this in detail.
Here's my suggestion, design an RF phase locked loop oscillator with discrete circuitry, get it working, then tap it with something solid.
You'll see all sorts of odd behaviour on the RF output unless you're very lucky, spectral components that appear, increased phase noise and generally crap performance!
PLL's are notoriously vibration sensitive.
Explain why.
Andy.
The signal from a CD mechanism is a high frequency analogue signal not a digital one. There's plenty of opportunity for it to be affected by a host of things, not least vibration, be that directly, or via secondary effects.
It certainly exists in electronics, so it's not impossible. Somewhere I have an LT data sheet (IIRC) on voltage references that actually has 'scope traces of the effect on output noise of tapping a capacitor with a pencil.
My guess is this is such a hard leap for you, because you obviously haven't looked at this in detail.
Here's my suggestion, design an RF phase locked loop oscillator with discrete circuitry, get it working, then tap it with something solid.
You'll see all sorts of odd behaviour on the RF output unless you're very lucky, spectral components that appear, increased phase noise and generally crap performance!
PLL's are notoriously vibration sensitive.
Explain why.
Andy.
What comes out of the CD player is indeed just digital. The analog comes out of the DAC.
In the context in which I said this, anyway. I am quite aware that the signal going to the amplifier is analog.
The argument about the PLL jitter is possible. I will see what I can find out about it. Has anyone done any actual LISTENING tests? The kind that a scientist would accept, not something that is influenced by psychoacoustic bias?
The most ideal way to this would to have two identical players. One is isolated inside of an mdf box, and the other is exposed to the sound field of the speakers.
This is most definitely something that can be found with an ABX test if it is there or not.
So far this quartz crystal jitter is the only thing I've heard so far that makes any logical sense of why it would be so necessary to isolate a CD player from vibration.
*****
Back to Meisner, there is absolutely nothing there other than well-written blather about wonderful the cryo-stuff is, all couched in the finest scientific language, but without any actual understanding of the principles of science. He says his listening tests show an improved airiness in the sound. He quotes all sorts of examples of cryo cooling, but none of the examples has much to do with explaining why the cooled cables perform better.
It is highly unlikely that any chemical or physical changes result from the cooling, from what I know about physics.
We are just supposed to believe him. This golden ear camp fall for the most complete nonsense sometimes. And unfortunately, this very often makes it hard to get credibility when something that actually can be heard is discovered, but since it is coming from these loonies, nobody even tests it for a long time, and progress is delayed.
In the context in which I said this, anyway. I am quite aware that the signal going to the amplifier is analog.
The argument about the PLL jitter is possible. I will see what I can find out about it. Has anyone done any actual LISTENING tests? The kind that a scientist would accept, not something that is influenced by psychoacoustic bias?
The most ideal way to this would to have two identical players. One is isolated inside of an mdf box, and the other is exposed to the sound field of the speakers.
This is most definitely something that can be found with an ABX test if it is there or not.
So far this quartz crystal jitter is the only thing I've heard so far that makes any logical sense of why it would be so necessary to isolate a CD player from vibration.
*****
Back to Meisner, there is absolutely nothing there other than well-written blather about wonderful the cryo-stuff is, all couched in the finest scientific language, but without any actual understanding of the principles of science. He says his listening tests show an improved airiness in the sound. He quotes all sorts of examples of cryo cooling, but none of the examples has much to do with explaining why the cooled cables perform better.
It is highly unlikely that any chemical or physical changes result from the cooling, from what I know about physics.
We are just supposed to believe him. This golden ear camp fall for the most complete nonsense sometimes. And unfortunately, this very often makes it hard to get credibility when something that actually can be heard is discovered, but since it is coming from these loonies, nobody even tests it for a long time, and progress is delayed.
Missed my point
NO!
What comes out of the mechanism (i.e. what is read from the disc) is analogue not digital. It's an analogue signal representing the digital data.
It's not simply a digital system, there's plenty of opportunity for jitter on the disc, the reading process and the conversion of eye-pattern to digital data to affect sound. If this translates to input jitter at the DAC it will be audible.
The fundamental issue is this doesn't matter if you stay in the digital domain, since time is a non-issue, within reason. A cd copied digitally doesn't change the DATA on the disc if the copy is succesful, but it can change the replay process in a CD player as the disc can (will, in most cases with a CD-R drive) have jitter added in the recording phase. Jitter only matter at the D-A process, unless extreme.
Try it, look at the eye pattern in a CDP with mastered and different copied discs - the difference is visible on a 'scope!
A CD player is a streaming system though, in which time is a critical factor.
Andy.
NO!
What comes out of the mechanism (i.e. what is read from the disc) is analogue not digital. It's an analogue signal representing the digital data.
It's not simply a digital system, there's plenty of opportunity for jitter on the disc, the reading process and the conversion of eye-pattern to digital data to affect sound. If this translates to input jitter at the DAC it will be audible.
The fundamental issue is this doesn't matter if you stay in the digital domain, since time is a non-issue, within reason. A cd copied digitally doesn't change the DATA on the disc if the copy is succesful, but it can change the replay process in a CD player as the disc can (will, in most cases with a CD-R drive) have jitter added in the recording phase. Jitter only matter at the D-A process, unless extreme.
Try it, look at the eye pattern in a CDP with mastered and different copied discs - the difference is visible on a 'scope!
A CD player is a streaming system though, in which time is a critical factor.
An externally hosted image should be here but it was not working when we last tested it.
Andy.
Hi,
No it does NOT.
A CD-ROM is just a blank writeable disc: Read Only Memory (or Media if you like)
Absolutely NOT.
Which has nothing to do whatsoever with a damaged data file on a CD.
CD-ROM can be written to using a few standards, these can be mixed on the same CD-ROM but none of those include a single byte of redundant data.
The standards go according to the YellowBook specifications.
Digital encoding allows the use of error correction codes, which are necessary to correct errors resulting from the manufacturing process and minor damage or marks which may occur from handling and use.
The result is that the amount of data stored on a CD is nearly four times the data needed to represent the audio only. But this is a small price to pay for a robust format that allows recordings to be played back free of clicks, hiss and other defects associated with analogue media.
Pretty basic perhaps but it's there alright...
So, unless you invented your own standards, I get the impression you're as confused as a barking bird here...
Tongue firmly in cheek, Peter....
Cheers,😉
No it does NOT.
A CD-ROM is just a blank writeable disc: Read Only Memory (or Media if you like)
Absolutely NOT.
Which has nothing to do whatsoever with a damaged data file on a CD.
CD-ROM can be written to using a few standards, these can be mixed on the same CD-ROM but none of those include a single byte of redundant data.
The standards go according to the YellowBook specifications.
Digital encoding allows the use of error correction codes, which are necessary to correct errors resulting from the manufacturing process and minor damage or marks which may occur from handling and use.
The result is that the amount of data stored on a CD is nearly four times the data needed to represent the audio only. But this is a small price to pay for a robust format that allows recordings to be played back free of clicks, hiss and other defects associated with analogue media.
Pretty basic perhaps but it's there alright...
So, unless you invented your own standards, I get the impression you're as confused as a barking bird here...
Tongue firmly in cheek, Peter....
Cheers,😉
Now we have already had this argument.
There are most definitely read errors on CDs (or even hard drives for that matter) but there is redundant data written so that error correction can detect these mistakes and fix them.
If the error correction fails, you usually get a really colossal mistake. You don't get little errors, since the error correction fixes 100% of the errors.
Since the CD data reading process is designed to cope with dirty disks exposed to the fingerprints or worse, the error correction redundancy is rather high. So it takes a pretty big error to mess it up. If there are any little errors caused by vibration of the disk, they are not not going to affect the actual recomposed digital data NOT ONE SINGLE WHIT, IOTA or SMIGEN.
There are most definitely read errors on CDs (or even hard drives for that matter) but there is redundant data written so that error correction can detect these mistakes and fix them.
If the error correction fails, you usually get a really colossal mistake. You don't get little errors, since the error correction fixes 100% of the errors.
Since the CD data reading process is designed to cope with dirty disks exposed to the fingerprints or worse, the error correction redundancy is rather high. So it takes a pretty big error to mess it up. If there are any little errors caused by vibration of the disk, they are not not going to affect the actual recomposed digital data NOT ONE SINGLE WHIT, IOTA or SMIGEN.
geewhizbang said:
Clear !
But these vibes migth cause other problem e.g. messing up the low jitter osc.
Well - then that was sorted out !
Shakti, anyone `????
/
Frank
You're wrong.
If you examine the various CD books you'll see that CD-DA (Audio, Red Book) and CD-ROM (Data, Yellow book) do have a different data format, the latter having more powerful ECC and more precise data addressing.
The physical parameters of CD-ROMs are identical to those defined in the Red Book. However CD-ROM discs differ from CD audio discs in two important ways: -
The data on a CD-ROM disc are divided into sectors containing user data and additional error correction codes.
The data are contained in files and so a file system is needed so that the required files can be accessed easily and quickly.
This does make a difference and is the reason early drives had trouble performing digital audio extraction with any accuracy - the positional information is very low resolution.
CD audio is a streaming, not random-access format.
Andy.
You're wrong.
If you examine the various CD books you'll see that CD-DA (Audio, Red Book) and CD-ROM (Data, Yellow book) do have a different data format, the latter having more powerful ECC and more precise data addressing.
The physical parameters of CD-ROMs are identical to those defined in the Red Book. However CD-ROM discs differ from CD audio discs in two important ways: -
The data on a CD-ROM disc are divided into sectors containing user data and additional error correction codes.
The data are contained in files and so a file system is needed so that the required files can be accessed easily and quickly.
This does make a difference and is the reason early drives had trouble performing digital audio extraction with any accuracy - the positional information is very low resolution.
CD audio is a streaming, not random-access format.
Andy.
Hi,
No I am not wrong.
Let's get this straight first of all: CD-ROM is not a data standard but the physical medium you can write to:
You could write CD-DA to CD-ROM for instance after which you'd have a CD with DA (digital audio) on it.
If you take that same CD-ROM you could also write DATA to it (files) in a number of formats including ISO 9660, JOLIET, MacIntosh HFS, etc.
What we call a CD-ROM is 9/10 just the medium with data files on it, the same medium with audio on it written as CD-DA standard we'd call an audio CD.
In both cases the discs are nothing more than CD-ROMs just the way it's addressed is different.
In all cases none of the DATA formats contain a single bit of redundant information, CD-DA written formats do.
That ECC is handled differently in both cases is true but in the case of raw data there no extra information actually written to CD-ROM (the medium) that can be used for EC contrary to DA.
Yes. I never stated anything to the contrary.
To recap the CD-DA Red-Book standard descibes the physical properties of the Compact Disc (CD-ROM) and the digital audio encoding.
Beyond that standard you have the Blue Book which does the same for Enhanced CD, aka CD-Extra.
For info:
Philips Intellectual Property & Standards,
Email: info.licensing@philips.com
URL: www.licensing.philips.com
Fax: +31-40-2732113
Cheers, 😉
No I am not wrong.
Let's get this straight first of all: CD-ROM is not a data standard but the physical medium you can write to:
You could write CD-DA to CD-ROM for instance after which you'd have a CD with DA (digital audio) on it.
If you take that same CD-ROM you could also write DATA to it (files) in a number of formats including ISO 9660, JOLIET, MacIntosh HFS, etc.
What we call a CD-ROM is 9/10 just the medium with data files on it, the same medium with audio on it written as CD-DA standard we'd call an audio CD.
In both cases the discs are nothing more than CD-ROMs just the way it's addressed is different.
In all cases none of the DATA formats contain a single bit of redundant information, CD-DA written formats do.
That ECC is handled differently in both cases is true but in the case of raw data there no extra information actually written to CD-ROM (the medium) that can be used for EC contrary to DA.
Yes. I never stated anything to the contrary.
To recap the CD-DA Red-Book standard descibes the physical properties of the Compact Disc (CD-ROM) and the digital audio encoding.
Beyond that standard you have the Blue Book which does the same for Enhanced CD, aka CD-Extra.
For info:
Philips Intellectual Property & Standards,
Email: info.licensing@philips.com
URL: www.licensing.philips.com
Fax: +31-40-2732113
Cheers, 😉
On error correction
CD error correction details
I don't know if this is 100% correct, but it certainly reads like it. To summarize, all CD:s have error correction.
Data CD-s have more correction than audio CD:s, whereas audio CD:s have some degree of error concealment.
Given the playback process (if ECC is properly implemented), it's quite hard to understand how jitter in the bit retrieval can carry through all the way to the DAC. On the other hand, that jitter in the clock that feeds the DAC might cause audible artifacts is not unlikely.
I will refrain from guessing whether Shakti stones or spikes have any effect on the clock jitter level.
Rune
CD error correction details
I don't know if this is 100% correct, but it certainly reads like it. To summarize, all CD:s have error correction.
Data CD-s have more correction than audio CD:s, whereas audio CD:s have some degree of error concealment.
Given the playback process (if ECC is properly implemented), it's quite hard to understand how jitter in the bit retrieval can carry through all the way to the DAC. On the other hand, that jitter in the clock that feeds the DAC might cause audible artifacts is not unlikely.
I will refrain from guessing whether Shakti stones or spikes have any effect on the clock jitter level.
Rune
Konnichiwa,
A CD-Rom is NOT writable.
Further, the Data is encoded on CD's (all of them) in tracks of "Pit's and Land" just as on magnetic Disks it is as north/south magnetisation.
The "File System" is a structure imposed on top of the raw "Pit/Land" or "Nort/South" individual data bit's (the noughts and zeros in effect). This means that a certain specific block of ones and noughts forms a "bedinging of track/file" marker and that then the data is written into the file. Just how it is written and what methodes of revoering errors is implemented depends upon hardware and software implementations and these are are different for CD Rom and Redbook CD.
Absolutely yes, RTFM.
The File a CD-ROM is damaged if a large enough number of data blocks are not recoverable and if the redundancy data fails to allow correction.
If a sufficient large number of data blocks are unreadable or read incorrectly with an Audio CD the error correction has already failed and must apply error concealement (I lump error corrction and error concealement into one mechanisms as this is how audio CD handels it).
CD-ROM = CD READ ONLY MEMORY
Meaning it cannot be written at all, you can only press it.
It seems you are erronously refer to the Writable CD-ROM, or more accuratly CD-WORM....
I may to re-read, however I remember the standard for DATA Files on CD-Rom to include reduant data.
One of us surely is.
http://www.cdrfaq.org/faq02.html#S2-17
"audio CDs use all 2352 bytes per block for sound samples, while CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data."
Hence CD-Rom uses 304 Bytes for every 2048 Bytes data as redudant data, or in other words around 15%. This data is REDUDANT as it is NOT the actual data but data other than that.
Again, RTFM.
Sayonara
fdegrove said:
A CD-Rom is NOT writable.
Further, the Data is encoded on CD's (all of them) in tracks of "Pit's and Land" just as on magnetic Disks it is as north/south magnetisation.
The "File System" is a structure imposed on top of the raw "Pit/Land" or "Nort/South" individual data bit's (the noughts and zeros in effect). This means that a certain specific block of ones and noughts forms a "bedinging of track/file" marker and that then the data is written into the file. Just how it is written and what methodes of revoering errors is implemented depends upon hardware and software implementations and these are are different for CD Rom and Redbook CD.
fdegrove said:
Absolutely yes, RTFM.
fdegrove said:
The File a CD-ROM is damaged if a large enough number of data blocks are not recoverable and if the redundancy data fails to allow correction.
If a sufficient large number of data blocks are unreadable or read incorrectly with an Audio CD the error correction has already failed and must apply error concealement (I lump error corrction and error concealement into one mechanisms as this is how audio CD handels it).
fdegrove said:
CD-ROM = CD READ ONLY MEMORY
Meaning it cannot be written at all, you can only press it.
It seems you are erronously refer to the Writable CD-ROM, or more accuratly CD-WORM....
fdegrove said:
I may to re-read, however I remember the standard for DATA Files on CD-Rom to include reduant data.
fdegrove said:
One of us surely is.
http://www.cdrfaq.org/faq02.html#S2-17
"audio CDs use all 2352 bytes per block for sound samples, while CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data."
Hence CD-Rom uses 304 Bytes for every 2048 Bytes data as redudant data, or in other words around 15%. This data is REDUDANT as it is NOT the actual data but data other than that.
Again, RTFM.
Sayonara
Kuei Yang Wang said:
Did you actually bother to read the entire paragraph from which you quoted a part? I suggest you do...
Rune
What do you call it then?
You're arguing silly semantics here but since we've started CD-ROM or CD-ROM XA is covered by the yellow book.
CD or CD-DA is the conventional description for red book discs it also covers CD-G, CD-TEXT, CD-G +MIDI, CD Single, CD Maxi Single, early Karaoke CD, CD Video Single (Extensions to CDDA).
CD-ROM is not the name used for the medium in the red book standard.
It covers the physical properties, but does not mention CD-ROM at all in this context.
Anyway, the point was you used your argument to try and repute Kuei's argument about the different formats having different error correction seemingly choosing to mis-interpret his obvious intentions by playing semantics.
Andy.
You're arguing silly semantics here but since we've started CD-ROM or CD-ROM XA is covered by the yellow book.
CD or CD-DA is the conventional description for red book discs it also covers CD-G, CD-TEXT, CD-G +MIDI, CD Single, CD Maxi Single, early Karaoke CD, CD Video Single (Extensions to CDDA).
CD-ROM is not the name used for the medium in the red book standard.
It covers the physical properties, but does not mention CD-ROM at all in this context.
Anyway, the point was you used your argument to try and repute Kuei's argument about the different formats having different error correction seemingly choosing to mis-interpret his obvious intentions by playing semantics.
Andy.
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