Quick Read: Variable bit rate encoding makes a tremendous difference in the audio quality results, certainly enough to justify -many times over- the slight file size increase . They noted that allowing for higher bit rate compression during more musically dense passages captures an astonishing amount of complexity while keeping the files sizes down to a minimum.

MP3 is a computer audio format used to create acceptable audio quality at reasonable file sizes. Remember that at a constant compression rate of 128kBps (kilo-bits-per-second) a 50MB wave file becomes a 5MB mp3 file. In January 2006 MaximumPC magazine conducted an audio quality test to find out if higher bit rate compression really pays off.

Four subjects -a hipster into electronica music, a curmudgeon selected for being a total skeptic, a pluralist or laid-back listener familiar with many musical styles, and an audiophile up on the technical limitation of the mp3 format were asked to bring in a track they were very familiar with and see if they could correctly identify the between the uncompressed (wave file), 320K, and 160k versions of the track.

The results: only one person was able to differentiate between the uncompressed and 160K encoded version of the tracks (at best) 50% of the time! Yes, individual results varied but none could get more than 6 out of 12 correct. The hipster scored lowest by only identifying the 3 versions of her track so she got 3 out of 12 correct. The curmudgeon also identified the 3 versions of the hipster s track plus 2 more finishing with 5 out of 12 correct (interestingly he was unable to identify the 3 versions of his own selected track.). The pluralist also successfully identified the three versions of her track plus 3 others so she got 6 out of 12 correct. Finally the audiophile identified the 3 versions of the pluralist s track plus 2 more (identifying only 1 version of his selected track) and ended up with 5 out of 12 correct. These results also indicate that being extremely familiar with the track and also the track genre (style, content type) are the most influential factors when correctly identifying a track.

In spite of these results the MaximumPC testers conducted some follow-up testing and did find that variable bit rate encoding makes a tremendous difference in the audio quality results, certainly enough to justify -many times over- the slight file size increase . They noted that allowing for higher bit rate compression during more musically dense passages captures an astonishing amount of complexity while keeping the files sizes down to a minimum .

This is exactly the reason we offer our products in the optimal MP3-VBR (variable-bit-rate) format.