Timbre change wav -> mp3

[afreshcupofjoe]

Do notice that mp3 does "things" to the song because it uses lossy codecing and majority of the loss happens at 13khz and above with 320 kbps, but with 128kbps you can actually hear that you lose a lot of hi mids too. Because of this, the sound changes, but the peaks will try to stay the same and the codec interpolates the peaks, but if they accidentally happen to be over the 0dbFS limit, they will sound like something that comes out of you after you eat.

Try this which I found out that helps in 90% of the cases: Normalize the wav to -0.6dbFS and then convert it to mp3 using LAME or some else quality mp3 codec and the difference shouldn't that drastic.

Definitely noticed this problem too. It only seems to happen on commercial cds that are EXTREMELY squashed. Normalizing to -1db seems to fix the problem. Never had this issue with my own recordings because I would never compress the master bus so much. It's so sad what they do to many commercial releases these days.