4 ms·

Rotating plastic that relies on sensitive optics? No thanks, that seems far from perfect for lossless, digital data. I will take a solid-state medium any day ov

by anc84 8y ago

Rotating plastic that relies on sensitive optics? No thanks, that seems far from perfect for lossless, digital data. I will take a solid-state medium any day over spinning discs.

tempodox 8y ago
“lossless, digital data” is a contradiction in terms if the source is analog. When converting analog to digital, resolution is finite.
- LordHeini 8y ago
  No it is not! As long as you stay in the frequency range of the Nyquist–Shannon sampling theorem the source signal is indeed lossless. There are a lot of misconceptions about this you should look it up. Don't forget, that a vinyl has frequency limits as well.
- sjwright 8y ago
  All practical analog audio signals are band limited and have a nominal noise floor. Given those characteristics, the conversion from analog to digital can be considered mathematically lossless. https://en.m.wikipedia.org/wiki/Nyquist–Shannon_sampling_theorem https://en.m.wikipedia.org/wiki/Nyquist–Shannon_sampling_the... Then you consider the fact that our own ears are band limited and dynamic range limited and you realise pretty quickly that CD audio at 16 bits 44100 Hz is, for all practical purposes, an objectively lossless audio format.
- throwaway2048 8y ago
  The mistake is thinking the precision of analog sound is infinite.
- adrianmonk 8y ago
  In this context, lossless refers only to what happens after the data is already digital. Some digital formats apply data compression the reverse of which doesn't recover the original bits exactly. Some digital formats (including CD) use no data compression or a form of compression that recreates exactly the same bits. It's similar to the difference between JPEG and PNG. There is a quality parameter when creating a JPEG because the decompressed image will not be exactly the same, but there is no such quality parameter for PNG because PNG will restore the exact value of every pixel.
throwaway2048 8y ago
Flash media has capacitance based charge that degrades with time, a CD will degrade approximately never.
- TheOtherHobbes 8y ago
  CDs do absolutely degrade. CD-Rs are so unreliable they're almost useless as an archival medium, and not a few commercial CD run had manufacturing defects which affected long-term stability. CDs are also imperfect. There are two levels of error correction. Both affect the sound. The only perfect format is digital storage of a lossless source such as a bit-perfect CD rip or direct digital master copy, with multiple copies in different locations.
  - ahartmetz 8y ago
    CD-Rs are not so bad if you don't write them at maximum speed (you'll still need to store them in a dark place / case). It is pretty well reported that writing at maximum speed causes higher initial error rate and worse longevity, yet most people don't even seem to consider the possibility to reduce speed.
- TazeTSchnitzel 8y ago
  Disc rot is, sadly, a thing, but in general commercially produced CDs are pretty reliable.
- stordoff 8y ago
  The possibility of getting a bad batch exists. Slightly different I know, but of the Warner HD DVDs I own, approximately 80% are now unreadable due to IIRC the glue used.
einr 8y ago
Rotating plastic that relies on sensitive optics? I mean, that sounds fragile when you put it like that, but in reality you can go to any thrift store and pick up a 1988 CD player and a 1982 CD and it will more than likely play perfectly. CD transport and decoding has been a solved problem for literally decades. CD is very, very robust as long as you handle the discs like an adult.
- marcosdumay 8y ago
  Perfectly is overstating it. You could take a CD pressed in 2002 directly from the store into a reader and many of the data blocks would already be corrupted. Audio CDs last for a while because they are not lossless. Data CDs have a lot of redundancy to try to fix that, but even then don't last for very long.
- MivLives 8y ago
  Unless your 1982 CD has rotted https://en.wikipedia.org/wiki/Disc_rot https://en.wikipedia.org/wiki/Disc_rot
- luigibosco 8y ago
  By "as long as you handle the discs like an adult" do you mean that dance you get to do while you hold the disc with your fingers around the edges, while you search for the case that either the little plastic ears broke off of so it doesn't hold the disc or the other cardboard case that scratches the disc when you put it in?

by anc84 8y ago

Rotating plastic that relies on sensitive optics? No thanks, that seems far from perfect for lossless, digital data. I will take a solid-state medium any day over spinning discs.

tempodox 8y ago

“lossless, digital data” is a contradiction in terms if the source is analog. When converting analog to digital, resolution is finite.

LordHeini 8y ago
No it is not! As long as you stay in the frequency range of the Nyquist–Shannon sampling theorem the source signal is indeed lossless. There are a lot of misconceptions about this you should look it up. Don't forget, that a vinyl has frequency limits as well.
sjwright 8y ago
All practical analog audio signals are band limited and have a nominal noise floor. Given those characteristics, the conversion from analog to digital can be considered mathematically lossless. https://en.m.wikipedia.org/wiki/Nyquist–Shannon_sampling_theorem https://en.m.wikipedia.org/wiki/Nyquist–Shannon_sampling_the... Then you consider the fact that our own ears are band limited and dynamic range limited and you realise pretty quickly that CD audio at 16 bits 44100 Hz is, for all practical purposes, an objectively lossless audio format.
throwaway2048 8y ago
The mistake is thinking the precision of analog sound is infinite.
adrianmonk 8y ago
In this context, lossless refers only to what happens after the data is already digital. Some digital formats apply data compression the reverse of which doesn't recover the original bits exactly. Some digital formats (including CD) use no data compression or a form of compression that recreates exactly the same bits. It's similar to the difference between JPEG and PNG. There is a quality parameter when creating a JPEG because the decompressed image will not be exactly the same, but there is no such quality parameter for PNG because PNG will restore the exact value of every pixel.

throwaway2048 8y ago

Flash media has capacitance based charge that degrades with time, a CD will degrade approximately never.

TheOtherHobbes 8y ago
CDs do absolutely degrade. CD-Rs are so unreliable they're almost useless as an archival medium, and not a few commercial CD run had manufacturing defects which affected long-term stability. CDs are also imperfect. There are two levels of error correction. Both affect the sound. The only perfect format is digital storage of a lossless source such as a bit-perfect CD rip or direct digital master copy, with multiple copies in different locations.
- ahartmetz 8y ago
  CD-Rs are not so bad if you don't write them at maximum speed (you'll still need to store them in a dark place / case). It is pretty well reported that writing at maximum speed causes higher initial error rate and worse longevity, yet most people don't even seem to consider the possibility to reduce speed.
TazeTSchnitzel 8y ago
Disc rot is, sadly, a thing, but in general commercially produced CDs are pretty reliable.
stordoff 8y ago
The possibility of getting a bad batch exists. Slightly different I know, but of the Warner HD DVDs I own, approximately 80% are now unreadable due to IIRC the glue used.

einr 8y ago

Rotating plastic that relies on sensitive optics? I mean, that sounds fragile when you put it like that, but in reality you can go to any thrift store and pick up a 1988 CD player and a 1982 CD and it will more than likely play perfectly. CD transport and decoding has been a solved problem for literally decades. CD is very, very robust as long as you handle the discs like an adult.

marcosdumay 8y ago
Perfectly is overstating it. You could take a CD pressed in 2002 directly from the store into a reader and many of the data blocks would already be corrupted. Audio CDs last for a while because they are not lossless. Data CDs have a lot of redundancy to try to fix that, but even then don't last for very long.
MivLives 8y ago
Unless your 1982 CD has rotted https://en.wikipedia.org/wiki/Disc_rot https://en.wikipedia.org/wiki/Disc_rot
luigibosco 8y ago
By "as long as you handle the discs like an adult" do you mean that dance you get to do while you hold the disc with your fingers around the edges, while you search for the case that either the little plastic ears broke off of so it doesn't hold the disc or the other cardboard case that scratches the disc when you put it in?