Where the Digital Audio Action Is
As a little digging into the contents of Table 2 quickly illustrates, the 10 formats listed in Table 1 don't begin to exhaust the complete collection of digital audio formats that you can find mentioned in the literature and on the Web. I made my cutoff based on formats that most readers were likely to recognize and by looking at the file formats supported on hard-disk and memory-based digital music players. In fact, iPod users aside, the most common such formats by far are MP3 (in a variety of guises, but all interchangeable) and Windows Media Audio (WMA). Figuring in the iPod community, it's also necessary to add Advanced Audio Coding (AAC) into the mix because that's the preferred format for the legions of such devices in wide use in the marketplace.
Table 2: Great Digital Audio References and Resources
Item/Title |
URL |
Comparison of digital audio formats |
|
Data formats and file extensions |
|
Digital audio primer |
|
Digital music formats |
|
MP3 Handbook: Digital Audio Formats |
|
Why variety is key in digital music formats |
Although there are arguments to be made for other formats (or particular varieties within the format mentioned in the previous paragraph), if you stick to one or more of these, you'll be very likely to be able to play your music on just about any device with digital audio playback capability. But because all of these popular formats can employ varying degrees of compression (although WMA includes an uncompressed format as well), it's important to understand that where sound is concerned, compression has two inevitable consequences, one good and the other not so good:
Compressing files makes them smaller. For devices with limited storage, smaller files mean that you can take more tunes with you. (Perhaps this applies more to RAM-based digital music devices, which seldom have even 1 full gigabyte of storage space, if that much.) Within reason, this is a good thing.
The various compression algorithms that these formats use are irreversible (also known as "lossy"), so the original sound cannot be restored to whatever fidelity it once enjoyed without going back to the original recording itself. Also, the more highly you compress a sound file, the less it sounds like the original (and, alas, the worse the overall fidelity becomes).
Of course, if you're downloading your music from the Web and storing it only in compressed format, you might have to buy the tune again if sound quality ever becomes an issue. On the other hand, if you own the CD or downloaded an uncompressed copy that's still in your possession, you can return to the original without too much difficulty.
This observation hides a subtle but important point: A lot of people have music in older formats such as vinyl records or some kind of recording tape. If you decide to rip that music into digital format, it might be worthwhile to create an uncompressed copy first and then rip a compressed version for use on a digital player of some kind. That way, you can always create another compressed version of the original from your uncompressed digital copy, instead of having to go back to the old, analog originaland how may of us are going to keep tape or record players around for too much longer anyway?
Also, if, like me, you have a home theater system with great audio fidelity, plus a car and a personal player, you might benefit from access to compressed and uncompressed versions of digital music. In the home theater setting, where audio quality is much more important, you can listen to your best-quality original digital music. In the car, where road or ambient noise diminishes sound quality anyway, or when listening to a personal player through mini headphones, a compressed version is just fine.
It might mean consuming more disk space than you otherwise would, but with 200-plus-gigabyte drives selling for less than $1 per gigabyte (and sometimes much less than that), keeping an uncompressed version as well as an MP3, WMA, or other more compact file around makes a lot of sense. Let your choice of file type and size come from your playback target, and you'll be able to strike the right balance between variety and sound quality.