Bringing Yourself Up to Speed with AAC, MP3, and Digital Audio - Understand the Wonders of the Audio CD
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You’ve probably never bothered to contemplate the wonders of the audio CD. But if you have, you may have realized that the CD is pretty wonderful. It’s not wonderful for the sound quality (although that was a great improvement on the cassette tapes and the vinyl LPs that preceded it) nor for its capacity (because other storage technologies, such as DVDs and magneto-optical disks, have far exceeded that), but for its standards-based universality.
You can buy a CD in just about any country on the planet, buy a CD player or CD drive in just about any other country, insert the CD, and play it. Depending on the quality of the CD player and the playback system, the audio should sound more or less as the artist and producer intended. As a result of this universality, CDs became widespread in the 1980s and remain the most popular medium for music distribution.
At first, record companies loved CDs more than consumers did, because CDs allowed them to sell to consumers the same music for a second or even a third time: the consumers had bought the music on LP; some of them had bought it on cassette tapes to play in their Walkmans; and now they could buy it once again on CD to play in their CD players. Better yet, because the CD was a newer, more faithful, and ostensibly more expensive-to-produce medium, the record companies could charge around twice as much for CDs as for LPs or cassette tapes. Since then, CD prices have come down a bit, but they remain far more profitable for the record companies than LPs or cassette tapes.
But soon, despite the prices, consumers began to love CDs as well, because CDs began to deliver on their promise of combining portability and acceptable durability with high-quality sound. And as you’ll know, by 2003 CDs had almost entirely replaced vinyl and cassettes as the medium on which people buy their music.
As mentioned in the previous section, starting in late 1999 and taking effect in 2000, Napster put a severe crimp in the dominance of the CD as the primary means of distributing music. Other file-sharing services followed. Around the same time, CD recording became easier, and recordable (and rewritable) CD media became very affordable. So consumers could easily share compressed digital audio files with friends and strangers alike on file-sharing services, or burn perfect copies of CDs to give to people they knew.
CD sales fell by 5 percent in 2001, by 7 percent in the first half of 2002, and by 9.3 percent in the whole of 2002. The Recording Industry Association of America (RIAA), which represents the record companies, has claimed that “illegal music downloading was the main culprit in the drop in sales” and has also put part of the blame on recordable CDs, even though it acknowledges that “the decline in consumer spending [has] played a role.”
Other commentators argue that other factors have almost certainly reduced CD sales as well. For example, the record industry released approximately 27,000 CDs in 2001 compared to nearly 39,000 CDs in 1999. Less choice, less appealing music: it makes sense that consumers would buy fewer CDs, especially if they have substantially less disposable income to spend on music thanks to the economic downturn.
In August 2002, the analysts at Forrester Research argued that the decline in CD sales was mostly attributable to the economic downturn. Forrester also argued MP3 had been good for the music business, because people who download MP3 files still tend to buy CDs. In effect, MP3 lets people preview music they might not otherwise have heard. If they like the music, they may well buy the CDs.
How CD-Protection Solutions Work (in Brief) In brief, and at the risk of generalizing wildly, CD-protection solutions work by corrupting the data on audio discs so the data can still be read by audio CD players but can’t be read by computer CD drives. Some high-end audio players, such as car CD players and DVD players, also have trouble reading some copy-protected audio discs.
key2audio uses a hidden signature on the disc to prevent playback on computers. Sony DADC claims the “audio part” of discs protected with key2audio fully complies with the Red Book standard because “no uncorrectable errors are used to protect the audio data.” However, because by design key2audio discs don’t work with Red Book–compliant CD drives and DVD drives, the discs themselves clearly aren’t Red Book–compliant. This might seem like a fine point, but it’s not—if the disc won’t play back on a CD drive, it’s not a CD.
According to Midbar Technologies, Cactus-200 Data Shield is an “engineering solution” (rather than a software solution) that “slightly alters the information on the CD [sic] in several ways while maintaining perfect audio quality.”
Consumer advocates put it differently: Cactus introduces errors in the data on the audio disc that require the error-correction mechanisms on the player to compensate. Using the error-correction mechanism on the player like this makes the disc less resistant to damage (for example, scratches), because the player will be unable to correct many damage-related errors on top of the deliberate copy-protection errors. The discs may also degrade more quickly than unprotected CDs. Some consumer advocates claim copy-protection solutions may also lead older or more delicate CD players to fail sooner than they would otherwise have done because they make the players work harder than unprotected CDs do, much as driving at full speed over rough roads will wear out your car’s suspension much more quickly than driving at the same speed on freeways will.
 This is chapter three of How to Do Everything with Your iPod & iPod Mini, by Guy Hart-Davis (McGraw-Hill/Osborne, ISBN 0072254521, 2004). Check it out at your favorite bookstore today.
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