WAV is the file format understood by computers that contains raw sound. These files, however, can be incredibly large and are not feasible for storage on a hard drive in this format. Though WAV may be a preferred medium for industry people such as producers or sound engineers, everyday listeners benefit greatly by compressing these files into a fraction of their size. The resulting MP3 format, originally intended for use in compressing motion pictures, eliminated humanly undetectable sound-data from the original recording and was typically 30 to 70% smaller. But how?
Obtaining WAV files
Nowadays, "ripping" CDs is as common as dubbing a cassette tape once was. A multitude of programs are now available that are fully capable of copying tracks off any disc and converting them into WAV files. The quality of the average WAV is equivalent to that heard on a compact disc, guaranteeing that the newly created copy is just as faithful as the original. Ways to preserve fidelity in the recording include keeping the source disc clean and protected properly with no scuffs or scratches, inside a jewel case or non-abrasive sleeve. Ripping the disc at a slower speed will allow the lens to interpret data more effectively. Music should ideally be copied from a disc at 4x or under. Any speed faster has been known to reveal audible imperfections when the song is played. If the flaw was not in the disc itself, it may help to re-rip the CD if such an undesirable result should occur.
Several freeware (free software) programs exist to accomplish the task of compressing audio, though users of Windows 7 and Vista will be delighted to know that the operating system itself comes equipped with its very own ripping/compressing utility made available through Windows Media Player.
Though methods vary, as do the individual ripping options, essentially all such programs are the same. Ultra high and low tones that our ears are naturally oblivious to are eliminated, effectively shrinking the file size to half or below. Exactly how much depends on "bit rate." This might be likened to the degree of optical zoom afforded by a camera, only in terms of sound. 128 is average, whereas 320, the maximum, is only slightly compressed. You will have to consult your program's instruction or help file to learn the exact method of compressing these files.
Factors to consider are how many songs you wish to compress and why. For day to day listening, you need not go too high, but in order to replicate the cleanest, crispiest tones, you may not want to skimp.