But before we begin, let us examine just how compression works. That way, you'll have at least half a clue when you impress your friends with wild jargon and useless facts. Sound file compression is achieved by removing inaudible information from the desired file, both above and below the human threshold of hearing. Each music format uses a unique mathematical algorithm to shrink the size of a raw file, generally in the compression range of 10 to 1. What this means is that a song that normally would take 50MB on your hard drive can be shrunk to somewhere near 5MB, and with a minimal loss of quality.
Smaller files are, of course, advantageous for both storage and transferring between computers.
Before music data is reduced, compact disc audio generally consists of 783,216,000 bytes. So, it takes more than 176K to hold just one second of CD stereo music. In our examples below, we highlight the entire range of bit rates in each of the popular formats and how well they compress the same amount of data. Along with a description and outline of a few key elements of each compression format, we've included a 27-second sample of classical music. Each example is saved in a variety of sampling rates, so you can download and sample them for yourself.