WMA - Windows Media Audio Files
Windows Media Audio files were Microsoft's answer to the MP3 compression format. They claim they are able to take the same quality file and squash it into half the space.
The truth is somewhat less impressive, and you of course can determine for yourself just how well WMA works on the CDs you own. There are free downloads for WMA compressors on the web, as well as free MP3 compressors. Be sure to use a new, high quality MP3 compressor and not an old one with older compressor technology.
The WMA compression does do a better job at lower bitrates, being able to better compensate for the relative lack of bits per second with quality compression. But as the bitrate increases, the MP3 software does just a good a job at capturing the essence of the music as the WMA software does.
With far more portable devices and software solutions supporting MP3s vs WMA, it might be wisest to use MP3 format for your audio files. For example, I had used WMA files myself for a while to get the slight space saving. But when I bought DVD creation software to turn my home movies into DVDs, I found it would only use MP3 files. So I had to re-rip many of my favorite CDs in order to include that music on my finished product.
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