In addition to which file type, another key factor determining audio quality is compression rate.

Your CD contains the highest quality audio, but takes up too much space. Compression is the process that squeezes your music into smaller files. While the type of file you opt for is important, compression rate is probably more important.

Compression is governed by the bitrate – how much data is discarded to secure the goal of a smaller music file. The higher the number, the less that gets lost.

Apple works to 128 kbps as a bitrate. That’s their basis for calculating the capacity of your iPod, it’s the quality of music you get from iTunes Music Store.

If you increase your file size (decrease the compression rate) you’ll get an appreciable sound improvement. You have a great deal of control when ripping in iTunes, but 192 kbps gives noticeably better music, 224 kbps better still.

So if you’re looking to improve the sound of your iPod (or digital music generally), the first step should be to up the compression rate from 128 (default) to 192 or 224 kbps.

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