This may sound like a joke, but it is not. LAME has many settings allowing the user to have fast conversion or higher quality. I found that iTunes, for example, is using a fast-algo that yields not that good results. MP3 coming from emusic.com, for example, are VBRs scanned at low speed. Those files sounds very good on my system compared to 320Kpbs with iTunes.

Settings for emusic.com "To encode the files on eMusic, we used LAME version 3.92. The import option that was used is -alt-preset standard"

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