MP3 Solution

There are a couple of technical tricks that can be used to find out the right solution.

  • You can use a spectrum analyzer software to find out which file has more harmonics than another, the most harmonics should indicate the wav file.
  • Due to some silence added in the beginning of the file during the conversion process the wav file is the only one that has a slightly different file size than the others. This way the wav can be identified for sure. Since it is possible to hear the 192kbps and 128kbps without a lot of trouble all files can be identified once the wav has been identified.
  • Listening to the MQ converted files of course made identifying the files easier.

The correct solution:

A: 320 KBPS
C: 192 KBPS
D: 128 KBPS

Results after filtering double votes from same IPs the results from the Poll:

A: 320 KBPS (8 for WAV, 6 for 320, 3 for 192, 2 for 128)
B: WAV (8 for WAV, 4 for 320, 6 for 192, 4 for 128)
C: 192 KBPS (7 for WAV, 4 for 320, 6 for 192, 1 for 128)
D: 128 KBPS (1 for WAV, 3 for 320, 2 for 192, 10 for 128)

The result show that the WAV, 320 and 192 were identified as the "WAV" equally and this indicates that (assuming that a part of it was coincidence) that at least about 65% of the listeners can not hear the difference between WAV and 320 Kbps and 192 Kbps.

The results clearly show that the 128Kbps mp3 can be identified with a high degree of certainty.

Interesting comments given on the subject:

  • If you decide to reconvert to another format it's not optimal to have an mp3 file
  • Some people say that emotionally they could feel the difference
  • Some people say that when changing the speed of the song the differences become more obvious (I didn't test)