I've read the past few posts as an argument as to whether audio CD:s have any error correction data at all, with Thorsten saying they don't. The document Thorsten quoted from says all CD:s have error correction data.
Now, if I have misinterpreted him, I apologise.
Could we just for the sake of discussion reach an agreement as to the issue of how error correction of audio CD:s work, without any excursions on the matter of the sound of those CD:s.
Rune
Now, if I have misinterpreted him, I apologise.
Could we just for the sake of discussion reach an agreement as to the issue of how error correction of audio CD:s work, without any excursions on the matter of the sound of those CD:s.
Rune
SEMANTICS?
Hi,
I'll give you semanitcs:
Definitions of CD-ROM on the Web:
(Compact Disk - Read Only Memory) - A computer storage medium which can store large amounts of information; generally used to distribute software or multi-media for use on computers with CD-ROM drives. CD-ROM disks look just like music CDs, and cannot be altered by a user.
www.getnetwise.org/glossary.php
stands for Compact Disc Read-Only Memory. A small plastic disk, similar to audio compact disks, used for storing information in digital format. The information is read from the disk by a small laser beam and displayed on a computer screen.
www.library.arizona.edu/rio/glossary.htm
Compact Disc-Read Only Memory. A compact disc formatted for data storage. Most CD-ROMs can store 650 megabytes of data.
iet.ucdavis.edu/glossary/
Compact Disk, Read Only Memory; a high-capacity secondary storage medium. Information contained on a CD is read-only. Special CD-ROM mastering equipment available in the OIT Multimedia Lab can be reserved for creating new CDs.
www.oit.ohio-state.edu/glossary/
Pronounced see-dee-rom, abbreviation of Compact Disc-Read-Only Memory. A type of optical disk capable of storing large amounts of data -- up to 1GB, although the most common size is 650MB (megabytes). A single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages. CD-ROMs are stamped by the vendor, and once stamped, they cannot be erased and filled with new data. To read a CD, you need a CD-ROM player. All CD-ROMs conform to a standard size and format, so you can load any type of CD-ROM into any CD-ROM player. In addition, CD-ROM players are capable of playing audio CDs, which share the same technology. CD-ROMs are particularly well-suited to information that requires large storage capacity. This includes color large software applications, graphics, sound, and especially video.
www.cert.org/homeusers/HomeComputerSecurity/glossary.html
Compact Disc Read Only Memory. A 3.5in disc that can store upto 650MB of data. Once written by the manufacturer, the contents of a CD-ROM are permannent and cannot be altered. Read using a CD-ROM drive.
www.davcomuk.co.uk/files/tech/glossary.htm
Compact Disc - Read Only Memory. An optimal disc that is used to store text, graphics and audio data for computer applications. The contents may not be changed or rewritten.
www.axis.com/corporate/corp/glossary_general.htm
(Compact Disc - Read Only Memory) - plastic discs with a reflective metal coating which are read by a small laser beam. They are similar to audio compact discs. The differences lie in the way that the signals are processed after being read. CD-ROMs may contain audio, but they are primarily used for text. Many sources of information are now available on CD-ROM. Compare with online.
www.royalroads.ca/coppul/glossary.html
(Compact Disk Read-Only Memory) A computer technology which allows information to be stored on a compact disk and accessed through a microcomputer.
www.libraries.uc.edu/help/how/tutorial/glossary.html
Compact Disk, Read-Only Memory. A type of storage device that looks just like an audio CD and stores as much data as a large hard disk (600MB), making it a popular means of distributing fonts, photos, electronic encyclopedias, games, and multimedia offerings. As the name indicates, however, you can't save or change files on a CD-ROM, only read them. Pronounced see-dee rom.
www-rohan.sdsu.edu/glossary.html
Compact Disc - Read Only Memory.
www.siemensauto.com/glossaries/its_glossary.html
Computer-readable information on compact disks. Farrell Library has a number of reference services on CD-ROM. A CD-ROM drive (reader) is a component of most multimedia systems and most modern software is delivered on CD-ROM. 50X is the current standard for CD drives. The number refers to the speed at which data can be read from the drive.
www.oznet.ksu.edu/ed_asi490/Glossary/cgw.htm
Abbreviation for Compact Disk-Read Only Memory. Sometimes called a compact disk; storage devices for databases that are accessed by microcomputer.
www.lib.umd.edu/UES/er_glossary.html
Compact Disk - Read-Only Memory, uses essentially the same technology as an audio CD in order to store large amounts of information in a very compact format
www.ex.ac.uk/its/glossary.htm
Compact Disc-Read Only Memory. A compact disc having programs, data,and other information for computer applications.
www.mo-forum.gr.jp/english/glossary/
A computer disk that can store large amounts of information and is generally used on computers with CD-ROM drives.
www.ed.gov/pubs/parents/internet/glossary.html
Compact Disk-Read Only Memory. A computer-based device for storage of information. A personal computer and a CD player are needed to read the information.
library.usask.ca/tutorials/basics/tutorial/gloss.html
A read-only-memory compact disk, used to store printed information such as periodical indexes. This disk is used with computer.
www.lib.umich.edu/ugl/info/glossary.html
A memory disc for computers that holds 550 megabytes of data. CD-ROM can be used to store computer programs, databases, books, video, pictures and sound. These media are stored on the same disc to create "multimedia" information and playback.
www.pbs.org/als/satsupport/glossary.htm
Compact Disk Read Only Memory
exp.telecomitalialab.com/exp-portal/glossary/
Compact Disk-Read Only Memory. An information technology used for storing and reading large amounts of information which is accessed through a computer. CD-ROMs look like the compact discs from a music store; but instead of storing music, they store text and other data
www.nps.gov/ccso/library/glossary.htm
Compact Disk - Read Only Memory
www.nbc-med.org/SiteContent/glossary.asp
Compact Disk Read Only Memory. A storage medium. Data are "stamped" onto the disk during the manufacturing process. The disk is read-only.
odwin.ucsd.edu/glossary/glossary.html
Compact Disk-Read Only Memory, a storage medium popular in modern computers. One CD-ROM can hold 600 MB of data.
www.intermark.org/im-glossary.html
An abbreviation of the term Compact Disc, Read Only Memory (A Compact Disc used to store digital data, such as large programs, that can be read by a computer).
recordingeq.com/GlosPubAE.htm
a compact disk that is used with a computer (rather than with an audio system); a large amount of digital information can be stored and accessed but it cannot be altered by the user
www.cogsci.princeton.edu/cgi-bin/webwn
Oh, BTW....A CD-ROM is still a CD-ROM even before it contains any data. It's only after the data is written and the session is closed that it becomes Read Only Memory.
How that data is actually transferred to that media is totally irrelevant to the definition of the MEDIUM itself.
Of course it doesn't.
It just doesn't apply and that's exactly what the issue is about: whether that medium contains raw data, picures, graphics you name it, the medium is still the same.
There just isn't any particular format of data written to that medium that would go by the format: CD-ROM.
Cheers, 😉
Hi,
I'll give you semanitcs:
Definitions of CD-ROM on the Web:
(Compact Disk - Read Only Memory) - A computer storage medium which can store large amounts of information; generally used to distribute software or multi-media for use on computers with CD-ROM drives. CD-ROM disks look just like music CDs, and cannot be altered by a user.
www.getnetwise.org/glossary.php
stands for Compact Disc Read-Only Memory. A small plastic disk, similar to audio compact disks, used for storing information in digital format. The information is read from the disk by a small laser beam and displayed on a computer screen.
www.library.arizona.edu/rio/glossary.htm
Compact Disc-Read Only Memory. A compact disc formatted for data storage. Most CD-ROMs can store 650 megabytes of data.
iet.ucdavis.edu/glossary/
Compact Disk, Read Only Memory; a high-capacity secondary storage medium. Information contained on a CD is read-only. Special CD-ROM mastering equipment available in the OIT Multimedia Lab can be reserved for creating new CDs.
www.oit.ohio-state.edu/glossary/
Pronounced see-dee-rom, abbreviation of Compact Disc-Read-Only Memory. A type of optical disk capable of storing large amounts of data -- up to 1GB, although the most common size is 650MB (megabytes). A single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages. CD-ROMs are stamped by the vendor, and once stamped, they cannot be erased and filled with new data. To read a CD, you need a CD-ROM player. All CD-ROMs conform to a standard size and format, so you can load any type of CD-ROM into any CD-ROM player. In addition, CD-ROM players are capable of playing audio CDs, which share the same technology. CD-ROMs are particularly well-suited to information that requires large storage capacity. This includes color large software applications, graphics, sound, and especially video.
www.cert.org/homeusers/HomeComputerSecurity/glossary.html
Compact Disc Read Only Memory. A 3.5in disc that can store upto 650MB of data. Once written by the manufacturer, the contents of a CD-ROM are permannent and cannot be altered. Read using a CD-ROM drive.
www.davcomuk.co.uk/files/tech/glossary.htm
Compact Disc - Read Only Memory. An optimal disc that is used to store text, graphics and audio data for computer applications. The contents may not be changed or rewritten.
www.axis.com/corporate/corp/glossary_general.htm
(Compact Disc - Read Only Memory) - plastic discs with a reflective metal coating which are read by a small laser beam. They are similar to audio compact discs. The differences lie in the way that the signals are processed after being read. CD-ROMs may contain audio, but they are primarily used for text. Many sources of information are now available on CD-ROM. Compare with online.
www.royalroads.ca/coppul/glossary.html
(Compact Disk Read-Only Memory) A computer technology which allows information to be stored on a compact disk and accessed through a microcomputer.
www.libraries.uc.edu/help/how/tutorial/glossary.html
Compact Disk, Read-Only Memory. A type of storage device that looks just like an audio CD and stores as much data as a large hard disk (600MB), making it a popular means of distributing fonts, photos, electronic encyclopedias, games, and multimedia offerings. As the name indicates, however, you can't save or change files on a CD-ROM, only read them. Pronounced see-dee rom.
www-rohan.sdsu.edu/glossary.html
Compact Disc - Read Only Memory.
www.siemensauto.com/glossaries/its_glossary.html
Computer-readable information on compact disks. Farrell Library has a number of reference services on CD-ROM. A CD-ROM drive (reader) is a component of most multimedia systems and most modern software is delivered on CD-ROM. 50X is the current standard for CD drives. The number refers to the speed at which data can be read from the drive.
www.oznet.ksu.edu/ed_asi490/Glossary/cgw.htm
Abbreviation for Compact Disk-Read Only Memory. Sometimes called a compact disk; storage devices for databases that are accessed by microcomputer.
www.lib.umd.edu/UES/er_glossary.html
Compact Disk - Read-Only Memory, uses essentially the same technology as an audio CD in order to store large amounts of information in a very compact format
www.ex.ac.uk/its/glossary.htm
Compact Disc-Read Only Memory. A compact disc having programs, data,and other information for computer applications.
www.mo-forum.gr.jp/english/glossary/
A computer disk that can store large amounts of information and is generally used on computers with CD-ROM drives.
www.ed.gov/pubs/parents/internet/glossary.html
Compact Disk-Read Only Memory. A computer-based device for storage of information. A personal computer and a CD player are needed to read the information.
library.usask.ca/tutorials/basics/tutorial/gloss.html
A read-only-memory compact disk, used to store printed information such as periodical indexes. This disk is used with computer.
www.lib.umich.edu/ugl/info/glossary.html
A memory disc for computers that holds 550 megabytes of data. CD-ROM can be used to store computer programs, databases, books, video, pictures and sound. These media are stored on the same disc to create "multimedia" information and playback.
www.pbs.org/als/satsupport/glossary.htm
Compact Disk Read Only Memory
exp.telecomitalialab.com/exp-portal/glossary/
Compact Disk-Read Only Memory. An information technology used for storing and reading large amounts of information which is accessed through a computer. CD-ROMs look like the compact discs from a music store; but instead of storing music, they store text and other data
www.nps.gov/ccso/library/glossary.htm
Compact Disk - Read Only Memory
www.nbc-med.org/SiteContent/glossary.asp
Compact Disk Read Only Memory. A storage medium. Data are "stamped" onto the disk during the manufacturing process. The disk is read-only.
odwin.ucsd.edu/glossary/glossary.html
Compact Disk-Read Only Memory, a storage medium popular in modern computers. One CD-ROM can hold 600 MB of data.
www.intermark.org/im-glossary.html
An abbreviation of the term Compact Disc, Read Only Memory (A Compact Disc used to store digital data, such as large programs, that can be read by a computer).
recordingeq.com/GlosPubAE.htm
a compact disk that is used with a computer (rather than with an audio system); a large amount of digital information can be stored and accessed but it cannot be altered by the user
www.cogsci.princeton.edu/cgi-bin/webwn
Oh, BTW....A CD-ROM is still a CD-ROM even before it contains any data. It's only after the data is written and the session is closed that it becomes Read Only Memory.
How that data is actually transferred to that media is totally irrelevant to the definition of the MEDIUM itself.
Of course it doesn't.
It just doesn't apply and that's exactly what the issue is about: whether that medium contains raw data, picures, graphics you name it, the medium is still the same.
There just isn't any particular format of data written to that medium that would go by the format: CD-ROM.
Cheers, 😉
Konnichiwa,
I actually CAN READ and YES, I have read the paragraph.
Now let me state my contentions:
1) CD and Data Media on CD have differing error correction mechanisms.
2) The error correction mechanism for CD is very basic.
3) If the basic error correction fails to recover the error the CD-Players Digital Processor applies one of several strategies of error concealement, which include interpolating samples and repeating complete frames of data.
Now lets see the paragraph in total.
Okay, contention 1:
"It is true that 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."
Contention supported by the source.
Contention 2:
"All of the data written to a CD uses CIRC (Cross-Interleaved Reed-Solomon Code) encoding. Every CD has two layers of error correction, called C1 and C2. C1 corrects bit errors at the lowest level, C2 applies to bytes in a frame (24 bytes per frame, 98 frames per sector). In addition, the data is interleaved and spread over a large arc."
This is a lot of verbiage, but it says in short that data is distributed such that adjecent samples end up in different areas of the CD and that there are basic checksums for pairs of bytes and for frames of 24Bytes. That's it.
For Data CD however "CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data."
So, contention supported by the source
Contention 3:
"If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable."
Contention supported by the source.
Now, exactly what where you referring to, if anything at all?
Sayonara
runebivrin said:
I actually CAN READ and YES, I have read the paragraph.
Now let me state my contentions:
1) CD and Data Media on CD have differing error correction mechanisms.
2) The error correction mechanism for CD is very basic.
3) If the basic error correction fails to recover the error the CD-Players Digital Processor applies one of several strategies of error concealement, which include interpolating samples and repeating complete frames of data.
Now lets see the paragraph in total.
Okay, contention 1:
"It is true that 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."
Contention supported by the source.
Contention 2:
"All of the data written to a CD uses CIRC (Cross-Interleaved Reed-Solomon Code) encoding. Every CD has two layers of error correction, called C1 and C2. C1 corrects bit errors at the lowest level, C2 applies to bytes in a frame (24 bytes per frame, 98 frames per sector). In addition, the data is interleaved and spread over a large arc."
This is a lot of verbiage, but it says in short that data is distributed such that adjecent samples end up in different areas of the CD and that there are basic checksums for pairs of bytes and for frames of 24Bytes. That's it.
For Data CD however "CD-ROMs use only 2048 bytes per block, with most of the rest going to ECC (Error Correcting Code) data."
So, contention supported by the source
Contention 3:
"If there are too many errors, the CD player will interpolate samples to get a reasonable value. This way you don't get nasty clicks and pops in your music, even if the CD is dirty and the errors are uncorrectable."
Contention supported by the source.
Now, exactly what where you referring to, if anything at all?
Sayonara
Eh?
Frank,
None of that is relevant to your argument, which was that CD-ROM is the medium for all CD formats.
It isn't.
An audio CD is pressed, and becomes simply a CD (or CDDA disc to be pedantic).
It wasn't a CD-ROM before that point and it doesn't become one afterwards, even if it's blue book.
A pressed DATA disc becomes a CD-ROM. Only yellow and orange book discs are CD-ROM's.
The blank discs you buy are CD-R, or CD-RW, what they then become, depends upon what you write to them.
As I said it's largely semantic.
Andy.
Frank,
None of that is relevant to your argument, which was that CD-ROM is the medium for all CD formats.
It isn't.
An audio CD is pressed, and becomes simply a CD (or CDDA disc to be pedantic).
It wasn't a CD-ROM before that point and it doesn't become one afterwards, even if it's blue book.
A pressed DATA disc becomes a CD-ROM. Only yellow and orange book discs are CD-ROM's.
The blank discs you buy are CD-R, or CD-RW, what they then become, depends upon what you write to them.
As I said it's largely semantic.
Andy.
Hi,
No, it's not.
Need I give the definition of "Compact Disk" as well?
Definitions of Compact Disk (CD) on the Web:
A data storage medium in which information is stored on a small, disk that is read by laser technology rather than by a magnetic transducer. CD-ROM is much like the audio CDs which hold sound data, a CD-ROM holds applications or data to be used by a computer. The computer can read the information contained on the CD-ROM; but because it is "read only," the user cannot record new information on it. CD-Recordable is a CD on which additional information may be recorded for future use. A special device is required to record data; however once recorded, it can be read by PC computers with appropriate software.
www.aits.uillinois.edu/glossary/glossaryc.html
A ROM medium that typically holds up to 1 GB of information.
199.247.245.42/afoster/Comp125/Term/Win2000Glossary.html
A relatively small optical disk on which text, data, sounds, visual images, and the like can be recorded digitally and then scanned, decoded, and transmitted by a laser beam to a computer monitor, television set, or playback device. See also AUDIOVISUAL RECORDS, OPTICAL DISK.
www.epa.gov/records/gloss/gloss02.htm
A nonerasable disk that stores digitized audio information.
web.umr.edu/~subra/cs235/files/Glossary.html
A small optical disk, normally 120mm across used to store audio. When used as a backing storage device to computer systems it is called CD-ROM which can contain audio, text and video.
www.highlandschools-virtualib.org.uk/secondary_curriculum/glossary.htm
a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser
www.cogsci.princeton.edu/cgi-bin/webwn
Notice the overlap between the two definitions?
Can I use a CD-ROM to hold DA? Absolutely!
Yes it is.
Not a single byte of redundant data is actually written to a CD-ROM. I do say : DATA.
The only "redundant" data a DATA file contains is the CRC cheksum, a checksum which was there before the file was actually written to CD and only serves as a verifier. A datafile with a wrong CRC can't be copied unless the CRC checksum error is deliberately ignored as in a byte to byte copy. The resultant file would be mostly unusable unless a data recovery program succeeds in recovering the error(s). Most of the time it isn't successful plainly because there is no redundancy to speak of and you could just as well win the lottery trying to guess.
No I'm not.
I strongly advise you to do so, starting with a glossary of terms would be nice.
Cheers,😉
No, it's not.
Need I give the definition of "Compact Disk" as well?
Definitions of Compact Disk (CD) on the Web:
A data storage medium in which information is stored on a small, disk that is read by laser technology rather than by a magnetic transducer. CD-ROM is much like the audio CDs which hold sound data, a CD-ROM holds applications or data to be used by a computer. The computer can read the information contained on the CD-ROM; but because it is "read only," the user cannot record new information on it. CD-Recordable is a CD on which additional information may be recorded for future use. A special device is required to record data; however once recorded, it can be read by PC computers with appropriate software.
www.aits.uillinois.edu/glossary/glossaryc.html
A ROM medium that typically holds up to 1 GB of information.
199.247.245.42/afoster/Comp125/Term/Win2000Glossary.html
A relatively small optical disk on which text, data, sounds, visual images, and the like can be recorded digitally and then scanned, decoded, and transmitted by a laser beam to a computer monitor, television set, or playback device. See also AUDIOVISUAL RECORDS, OPTICAL DISK.
www.epa.gov/records/gloss/gloss02.htm
A nonerasable disk that stores digitized audio information.
web.umr.edu/~subra/cs235/files/Glossary.html
A small optical disk, normally 120mm across used to store audio. When used as a backing storage device to computer systems it is called CD-ROM which can contain audio, text and video.
www.highlandschools-virtualib.org.uk/secondary_curriculum/glossary.htm
a digitally encoded recording on an optical disk that is smaller than a phonograph record; played back by a laser
www.cogsci.princeton.edu/cgi-bin/webwn
Notice the overlap between the two definitions?
Can I use a CD-ROM to hold DA? Absolutely!
Yes it is.
Not a single byte of redundant data is actually written to a CD-ROM. I do say : DATA.
The only "redundant" data a DATA file contains is the CRC cheksum, a checksum which was there before the file was actually written to CD and only serves as a verifier. A datafile with a wrong CRC can't be copied unless the CRC checksum error is deliberately ignored as in a byte to byte copy. The resultant file would be mostly unusable unless a data recovery program succeeds in recovering the error(s). Most of the time it isn't successful plainly because there is no redundancy to speak of and you could just as well win the lottery trying to guess.
No I'm not.
I strongly advise you to do so, starting with a glossary of terms would be nice.
Cheers,😉
Frank,
You shouldn't believe everything you read on the Web. Note none of those definitions come from the standards documents.
The blank discs are CD-R(W) or CD-R(W) Audio, a blank CDDA doesn't exist.
Well, it may, but it's useless, like this discussion 😉
Andy.
You shouldn't believe everything you read on the Web. Note none of those definitions come from the standards documents.
The blank discs are CD-R(W) or CD-R(W) Audio, a blank CDDA doesn't exist.
Well, it may, but it's useless, like this discussion 😉
Andy.
Hi,
That doesn't make them false per se.
I already gave a link to where to get the standards and some of the links I provided contain links to the IEC.
Precisely. They're all Compact-Disks anyway.
They do exist but they're in no way different than the others, other than the price you'd pay for them as it already includes a fee that goes to the RIAA.
At least that how it goes down here. Some of them are of higher quality and optimized for audio use but that's all there's to them.
Cheers,😉
That doesn't make them false per se.
I already gave a link to where to get the standards and some of the links I provided contain links to the IEC.
Precisely. They're all Compact-Disks anyway.
They do exist but they're in no way different than the others, other than the price you'd pay for them as it already includes a fee that goes to the RIAA.
At least that how it goes down here. Some of them are of higher quality and optimized for audio use but that's all there's to them.
Cheers,😉
uspto.gov
Yeah so if you read the patent info it mentions a permanent maget. Also the only claim that is made on the patent is that it reduces EMI. It's no mystery that a field will effect EMI. I have been on service calls plenty of times where a chuches choir mic lines pick up radio stations. I didn't use Shakti stuff but little cylenderical magnets that clip around the wire and the noise is gone. I simply used that as a demonstration to upgrade the wiring from cheap belkin install stuff to more expensive kanari stuff with a better sheilding. This is not "improving audio resolution" as Shakti would have you believe, but reducing EMI.
Yeah so if you read the patent info it mentions a permanent maget. Also the only claim that is made on the patent is that it reduces EMI. It's no mystery that a field will effect EMI. I have been on service calls plenty of times where a chuches choir mic lines pick up radio stations. I didn't use Shakti stuff but little cylenderical magnets that clip around the wire and the noise is gone. I simply used that as a demonstration to upgrade the wiring from cheap belkin install stuff to more expensive kanari stuff with a better sheilding. This is not "improving audio resolution" as Shakti would have you believe, but reducing EMI.
Re: uspto.gov
Alas the Randi thread comes full circle ..... again. Sau..ce, I commend you for reading the patent. And thanks for your note about EMI. Sorry, guys, demonstrating the audibility of EMI reduction does not constitute demonstrating the paranormal. No million bucks.
Whoa! There's a UFO outside my work window! Holy cow it's HUUUUUUGE!
sauuuuuce said:
Alas the Randi thread comes full circle ..... again. Sau..ce, I commend you for reading the patent. And thanks for your note about EMI. Sorry, guys, demonstrating the audibility of EMI reduction does not constitute demonstrating the paranormal. No million bucks.
Whoa! There's a UFO outside my work window! Holy cow it's HUUUUUUGE!
fdegrove said:
Actually, that's true. Now that I think of it, probably the biggest UFOs on record blew up parts of Los Angeles and the White House etc not so many years back. Actually, was that in a movie?
I actually saw into the window of the one that hovered outside my work window. I swear to The Deity I saw Shakti stones on top of Parasound amplifiers inside the control room. But here's the hitch: there were no speakers. Is that freaky or what?
aliens
You would think that with all of the adavanced technologies that aliens would a have a far superior method of reducing EMI. What does intergalactic shipping run these days any way? Probably more than the shakti stones are worth...............if only we could get inside and remove the stones we could conquer these aliens once and for all.
You would think that with all of the adavanced technologies that aliens would a have a far superior method of reducing EMI. What does intergalactic shipping run these days any way? Probably more than the shakti stones are worth...............if only we could get inside and remove the stones we could conquer these aliens once and for all.
I think you are getting confused again. A few variables, such as a bad pit, or a different disk brand, or positional changes caused by the multi-speed disk drive are going to cause the positions of the pits to vary quite a bit on copies.
But the data is read in from a source disk, the error correction bits do their thang, and a perfect digital data stream is created. It then gets written back to the disk with new error correction code and this can also also be different, but as long as the pits are written in a format that is understood by the target player the data on the copy is an identical perfect copy.
The DAC will receive exactly the same digital stream from either disk. No matter how many times you copy the disk, unless one off the copies is so bad that an outright, nasty error is made that the error correction cannot fix.
As far as the time dependent nature of the stream, the first generation players could barely keep up with the data stream. Memory was shockingly expensive, so they have very small buffers. These days, I would suspect that even rather cheap players have plenty of extra disk speed and memory buffer so it can read the disk several times where an error is detected and very often fix it. That is essentially how skip control works on a Walkman or a automotive CD player. They just have a 1 meg buffer.
The only thing you have left is the effect of vibrations on the quartz crystal inside the unit. I remain very dubious about this explanation but it could be possible.
Everything else, including the better sound of cry'oed CD, cannot be explained the way you are attemping here. You are greatly misunderstanding the process of CD writing and reading if you don't understand that copies are either perfect or have gross mistakes when the error correction fails.
There is no way to explain the slight changes you are describing other than Psychoacoustics, if you continue to try to explain this as errors in reading the pits.
Konnichiwa,
No consumer CD Player Chiset works like that. All CD-Players (excluding some for mobile use) operate SYNCRONOUS. There is no re-read, no memory buffer, no nothing. You keep making assumptions and you keep a shocking ignorance of facts.
Please make sure you know what you are talking about before you do.
So, we are back to one pass trying to correctly identify "Pit" or "Land". If at that exact point the disk surface is somewhat out of focus (because the disk is vibrating more than allowable) this reading of the "Pit" or "Land" will give inaccurate results. The inaccuracies may very be enough to exceed the very basic and primitive error correction, forcing the Error Correction circuitry to switch to error concealement.
Simple, straightforward and plain.
Now you could rip the CD to a Hard Disk with EAC set to "paranoid" and then compare the same data streamed from a CD player into the S/P-DIF input of your card and record that to HD. Then compare the files and note just how much the ripped CD differs from the one played via a syncronous opertaion CD Player.
You could then start scratching a CD burned for test purposes and play that and do the same process....
How about you do some actual research instead of asserting how things should be based on your irrational believe?
Sayonara
geewhizbang said:
No consumer CD Player Chiset works like that. All CD-Players (excluding some for mobile use) operate SYNCRONOUS. There is no re-read, no memory buffer, no nothing. You keep making assumptions and you keep a shocking ignorance of facts.
Please make sure you know what you are talking about before you do.
So, we are back to one pass trying to correctly identify "Pit" or "Land". If at that exact point the disk surface is somewhat out of focus (because the disk is vibrating more than allowable) this reading of the "Pit" or "Land" will give inaccurate results. The inaccuracies may very be enough to exceed the very basic and primitive error correction, forcing the Error Correction circuitry to switch to error concealement.
Simple, straightforward and plain.
Now you could rip the CD to a Hard Disk with EAC set to "paranoid" and then compare the same data streamed from a CD player into the S/P-DIF input of your card and record that to HD. Then compare the files and note just how much the ripped CD differs from the one played via a syncronous opertaion CD Player.
You could then start scratching a CD burned for test purposes and play that and do the same process....
How about you do some actual research instead of asserting how things should be based on your irrational believe?
Sayonara
Kuei Yang Wang said:
Well ...
From :http://www.marklevinson.com/products/overview.asp?cat=cd&prod=no390s
"Each bit of the digital audio signal is stored momentarily just prior to its transmission to the digital processor. The reference clock determines the precise moment when each bit is released from this memory buffer. This purely electronic process virtually eliminates transport-related jitter, whether of mechanical or electrical origin. Of course, another bit must be ready to be loaded into the buffer as the current bit leaves on its way to the processor. For this reason, the same crystal oscillator that controls flow of information out of the memory buffer also directs the digital servo that sets the rate at which data flows into the buffer.
By placing the all-important reference clock in the final stage of the transport section, and slaving the mechanical subassemblies to it rather than the other way around, the signal presented to the digital processor section of the No.390S is uncontaminated by electrically- or mechanically-induced jitter. The sonic advantages of this design are immediately apparent in the stunning clarity, warmth and dynamic contrasts exhibited by the No.390S."
KYW, one day I thing You will find Your self confidence a burden.
/
Someone has already explained over and over that the error correction on CDs is not as "basic" as your theories allow.
Secondly, even small errors in reading the CD data are very audible. You know a lot of stuff, but it is mostly wrong.
I would suspect that most home audio players have buffers and at least 2x readers, because a player that reads a lot of disks well without problems is going to sell better than one known to be picky. These days, a 1 meg buffer and a 2x motor are not going to add anything to the cost of the drive.
Secondly, even small errors in reading the CD data are very audible. You know a lot of stuff, but it is mostly wrong.
I would suspect that most home audio players have buffers and at least 2x readers, because a player that reads a lot of disks well without problems is going to sell better than one known to be picky. These days, a 1 meg buffer and a 2x motor are not going to add anything to the cost of the drive.
Konnichiwa,
Yes, this "Buffer" stores each bit after read. Nevertheless the data extraction is still sequential and essentially syncronous.
The Buffer is usally a few kB. Please peruse the datasheets for any funloving standard CD Processor, evaluate how much memory is on board and how it works.
Hardly. Contrary to believers I happen to KNOW. As I know proof can be supplied easily. Here a link to a Datasheet of a standard CD processor for your personal eludication and to reduce the degree of your shocking ignorance:
http://www.semiconductors.philips.com/acrobat/datasheets/SAA7327_2.pdf
This among other notes also lists the difference between standard operation and use with external memory and how this afffects reads and operation. It also covers the error correction operation in detail.
Basically, as they used to say in the old Millenium - RTFM and shut up till you have.
Konnichiwa
TNT said:
Yes, this "Buffer" stores each bit after read. Nevertheless the data extraction is still sequential and essentially syncronous.
The Buffer is usally a few kB. Please peruse the datasheets for any funloving standard CD Processor, evaluate how much memory is on board and how it works.
TNT said:
Hardly. Contrary to believers I happen to KNOW. As I know proof can be supplied easily. Here a link to a Datasheet of a standard CD processor for your personal eludication and to reduce the degree of your shocking ignorance:
http://www.semiconductors.philips.com/acrobat/datasheets/SAA7327_2.pdf
This among other notes also lists the difference between standard operation and use with external memory and how this afffects reads and operation. It also covers the error correction operation in detail.
Basically, as they used to say in the old Millenium - RTFM and shut up till you have.
Konnichiwa
I have compared an EAC ripped track with a track streamed from a transport during low, moderate, and high levels of vibration after removing all frame and subcode data (i.e., comparing .wav files without any headers). It wasn't completely scientific in that I didn't document my procedure, try to isolate all variables, or have others review my result, but it surely satisfies KYW's criteria of knowing rather than believing. And from that test, I KNOW that it takes rather high levels of vibration to produce read errors beyond the error correction ability of the transports I used, and I KNOW that it is vastly more likely that when such errors occur they produce large time blocks of muted signal. Not once did I find single bit errors in the stream due to vibration. To suggest that vibration could cause a subtle (which usually means correlated) change in the subjective quality of a CD is really stretching things, and to me sounds like the musings of someone who hasn't done an experiment themselves.
From my experience, vibration issues result in muted output, as the threshold of error correction is surpassed simultaneously for a large number of frames, while small smudges and scratches can result in the single bit interpolations that KYW speaks of. Microphony induced quality change is something I categorizes as impossible when related to disc vibration. As for clock jitter, as always I remain skeptical but open minded.
From my experience, vibration issues result in muted output, as the threshold of error correction is surpassed simultaneously for a large number of frames, while small smudges and scratches can result in the single bit interpolations that KYW speaks of. Microphony induced quality change is something I categorizes as impossible when related to disc vibration. As for clock jitter, as always I remain skeptical but open minded.
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