Quote:
Originally Posted by ratinox
CD-DA has a lot of odd compromises. Like how the recording time is 74 minutes, 33 seconds allegedly because that's the duration of a particular recording of Beethoven's Ninth Symphony.
Again, because the recording layer on CD-R and DVD-R is an organic material. Quickly degrades when exposed to oxygen.
Some brands are superior, as ownedbycats discovered. Verbatim and JVC/Taiyo-Yuden have the best reputations for both recording reliability (few/no coasters) and durability.
MO media should last forever barring physical damage. The metallic recording layer is inert, and it's non-magnetic except when under heated phase change conditions.
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I know that a Red Book CD doesn't have a file structure because at the time it was created that wasn't a concept. A Red Book CD stores the audio as one continuous groove, similar to the way audio is stored on an LP/45/78. It also contains a Table of Contents (TOC) that tells it where each track is on the disc. This is why Red Book CDs are gapless, the audio itself doesn't have gaps (unless silence is put in the source audio).
In a way, it is similar to the Minidisc which contains a TOC to tell the player where the tracks are. That's why you can delete and reorder tracks on a Minidisc. The tracks are recorded in a manner like on a floppy disc and the TOC tells it where each track is. Reordering the tracks just involves rewriting the TOC. If you delete a track on a Minidisc the track is not actually deleted, instead the recorder just deletes the track and it's space from the TOC and that space is freed up for future use and it may eventually be overwritten. However, that's why it is critical to ensure that the TOC can be properly written, if it is not all of the tracks could be lost.
As far as the maximum playing time on a Red Book CD, if you push everything to the absolute limit of the Red Book Standard without violating it, it is possible to fit almost 80 minutes of audio on a CD. However, the Red Book Standard doesn't establish a maximum amount of audio on a CD, just the standards for the CD itself (thickness diameter of the disc, the tolerances for the data recorded to the disc, and so on). This is why DualDiscs ("CD" on one side, DVD on the other) cannot be legitimately called a CD because the disc is slightly thicker (IIRC it is 4 microns thicker than the standard CD).
Concerning the 74-minute limit for audio, I think it was established as safe standard to deal with the limitations of the technology. Later, as the technology was improved it was possible to fit more audio on the CD without violating the Red Book Standard.
Concerning CD-Rs themselves, I don't consider them a long-term storage option. Instead, I see them as almost disposable. If one fails, I just burn another one.