Here is some information on different MP3 encoding settings in I-Tunes and their effect on the file size of the imported song.

The first song I imported was Emiliana Torrini’s Sunny Road, which comprises of her singing and some accoustic guitar accompaniement.

Artist          Track Length         Encoder                      File Size

Emiliana     3:04                      Wav                                 31 MB

Emiliana     3:04                      Aiff                                  31 MB

Emiliana     3:04                      MP3     320 kps            7.04 MB

Emiliana     3:04                      MP3     192 kps            4.22 MB

Emiliana     3:04                      MP3     160 kps            3.52 MB

Emiliana     3:04                      MP3     128 kps            2.81 MB

The next song I imported was Fluke’s ‘Groovy Feeling’ which is a electronic dance track.

Artist          Track Length         Encoder                      File Size

Fluke          4.03                      Wav                             40.9 MB      

Fluke          4.03                      Aiff                              40.9 MB

Fluke          4:03                      MP3     320 kps           9.29 MB

Fluke          4:03                      MP3     192 kps           5.57 MB

Fluke          4:03                      MP3     160 kps           4.64 MB

Fluke          4:03                      MP3     128 kps           3.71 MB

Fluke          4:03                      MP3       64 kps           1.86 MB

Fluke          4:03                      MP3       32 kps            953 KB

Fluke          4:03                      MP3       16 kps            457 KB

Listening Quality

The most important factor for most people will not be file size so much as how good does the MP3 sound. 128 kps is a setting a lot of people seem to favour and 128 kps MP3s sound very good.

The difference between 128 kps and the higher settings is very subtle, but perhaps best described as ‘the music sounds as if it has more room to breathe’, whereas a 128 kps can sound slightly constrained although a listener might struggle to put their finger on the difference between them. Some people may favour the 128 kps MP3 file because the music sounds closer !