Audio Files - MP3 (Poorly Compressible)

Compression Rate

In this difficult fileset, WinRK was the undisputed compression leader at its Maximum setting. Next up was Squeez, also at its Maximum setting. They were followed up by SBC Archiver (at all three settings) and WinRK at its Normal setting. The other compressors were not too far behind though.

The worst compressor was ARJ32 at its Fast setting. It only managed a very poor 0.13% compression rate. However, that was still better than WinRK (Fast setting) and StuffIt Deluxe (at all settings) which did not compress the fileset at all. In fact, they created an archive that was slightly larger than the fileset.

Compression Speed

Thanks to its utter refusal to compress MP3 files, StuffIt Deluxe (at all three settings) was the fastest compressor by far. Oddly enough, WinRK (Fast setting) which also refused to compress the files was much slower. In fact, ARJ32 (Fast setting) which did compress the fileset, albeit rather poorly, was much faster than WinRK.

Although WinRK was good at compressing these files, it was the slowest compressor by a ridiculous margin. Even Squeez at its Maximum setting was 4.8X faster than WinRK at its Normal setting.

Compression Efficiency

The compression efficiency rating is a simple way to evaluate the efficiency of each data compressor. This way, we can see which compressor can save the most space in the least time.

Please note that a higher efficiency rating does not mean the compressor is better. It just means the compressor has a better compression-to-speed ratio. A more efficient compressor is, of course, always more desirable than a less efficient one.

gzip, at all settings, was undeniably the most efficient compressor of the lot. Both WinRAR and WinZip at their Fast settings were also amongst the most efficient compressors of MP3 files. Close behind is ARJ32 at both Normal and Maximum settings.

Thanks to its extremely slow compression speed, WinRK was naturally the most inefficient compressor of this fileset. StuffIt Deluxe did not compress the fileset at any setting and actually created a slightly larger archive. Hence, the negative efficiency score.