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Vinyl To Signal the End for CDs?
PJ1216 writes to mention that vinyl seems poised to make a comeback in the music industry. Some are even predicting that this comeback coupled with the surge in digital music sales could possibly close the door on CDs. "Portability is no longer any reason to stick with CDs, and neither is audio quality. Although vinyl purists are ripe for parody, they're right about one thing: Records can sound better than CDs. Although CDs have a wider dynamic range, mastering houses are often encouraged to compress the audio on CDs to make it as loud as possible: It's the so-called loudness war. Since the audio on vinyl can't be compressed to such extremes, records generally offer a more nuanced sound. Another reason for vinyl's sonic superiority is that no matter how high a sampling rate is, it can never contain all of the data present in an analog groove, Nyquist's theorem to the contrary."
This statement is true, but completely irrelevant. The fact that a recording medium is analog does not mean that it is better at accurately recording and reproducing a sound than a digital medium. Magnetic tapes are also analog recordings. Putting a pencil on a string, hanging it next to a speaker, and having it draw a line on a moving sheet of paper is also an analog recording.
It's true that a digital recording can never contain the amount of data in a vinyl groove, but who is saying that all the data in a vinyl groove is more of an accurate representation of all the data extant in the original sound wave than a digitally sampled recording?
This is similarly irrelevant. Compression is a way of altering a sound wave, and has nothing to do with the final recording medium. Overcompression is a problem, but this is not an argument for vinyl over CD--it's just a comment on postprocessing techniques.
For one thing, vinyl has always had a loudness standard: the bigger you make the grooves, the fewer can fit on the record. So LPs were most often mastered at levels appropriate for a 24 minute side. (Extended singles for club play, which have fewer songs on them, are often mastered louder.) Compact Disc Digital Audio, on the other hand, never had a concrete definition of the playback volume.
CD is more portable than vinyl and is often listened to in a moving environment. The loudness race started when portable audio players such as Sony Discman and car units first came out. Some used a cheap op-amp to drive cheap headphones; others were car units that played over the radio. Record producers realized that end users could barely hear Dire Straits' Brothers in Arms over environmental noise, and they pushed mastering engineers to push the levels hotter.
Also, vinyl equalizes the bass down before recording and equalizes it back up in the player's preamp, based on a standardized New Orthophonic preemphasis curve. The limiter algorithms to overamplify an audio signal while fitting it into [-1..1] in the flat-equalized time domain of CD are not optimal for a time domain equalized in New Orthophonic. It's the producer's job to approve a master, and hearing these suboptimal results on vinyl might encourage an ambitious producer to back off on the demands to the mastering engineer.
Sorry mwvdlee, you are wrong. Acording to Nyquist, EVERY signal that has a limited bandwidth (don't know if that's the correct english term), that means it contains no frequencies above a certain limit frequency, can be totally reconstructed out of a sampled signal with double that limit frequency as sampling rate. This is a perfect reconstruction if you leave noise floor out of the equation. With 24 bit or even 16 bit per sample the noise floor is practically unhearable and much better than on a vinyl record.
Please, read up a bit about digital signals and the Nyquist theorem, it is counter-intuitive, but it works. There are no "edges" in a reconstructed (played) digital signal!