Do You Hear Me Now?
Every so often someone takes up the challenge of deciding which audio codec is the best. The latest is ExtremeTech and their review (see it here) of MP3, Ogg Vorbis, AAC, and WMA.
According to their results, which varies by bit-rate (they used 64, 128, and VBR set at 98 percent), the best is...now wait for it...dependent on several factors.
Those factors boil down to what hardware are you using. For example, if you are using a flash memory based product that has very little storage you may need to compress at 64K. On the other hand, if you are storing your music on a 5TB array you can encode pretty much at any rate you want (including no compression at all). On the other hand, should you choose the ubiquitous Apple iPod, you only have one choice, albeit a pretty good one based on the results.
The results in the table below are the geometric means of the ratings used. Each subject rated the sample from 1 through 5 with the higher number meaning better sounding. The numbers below are the overall aggrate of four different music samples:
| Codec | 64k | 128k | VBR |
| MP3 | 1.44 | 4.06 | 3.82 |
| WMA9 | 3.15 | 4.27 | 4.10 |
| Ogg Vorbis | 3.29 | 3.94 | 3.88 |
| AAC | 2.97 | 4.27 | N/A |
So, if you are forced to encode at 64k, use Ogg Vorbis (assuming your hardware supports it, which many do not, otherwise, use WMA). If you can encode at 128k, use WMA9 or AAC. It is difficult to recommend VBR since the resulting file size is about twice that of 128k while the scores, albeit subjective as they are, are lower than 128k. YMMV.