> I just had a quick peek through mpg123 and didn't see anything about > de-emphasis. If players ignore it, why put it in the encoder? > I saw that too and according to the answers of Ambrose Feinstein and Gabriel bouvigne, preemphasis was just used for analog recordings. Since it really is marginal (or now inexistant on CD), nobody bothered to implement it. The extract of "Principles of Digital Audio" implies that CD players have an integrated deemphasis function. On my Mac, Quicktime does all the job to extract tracks from CD so I just don't know if it apply a deemphasis filter in the rare cases where it is necessary. If ISO put the emphasis flag, it was probably necessary at the time the spec was decided but not today. Another question : il i want to convert an old metal K7(analog recording, but very good sound) to mp3 files, should i consider that deemphasis must be applied ? Lionel -- MP3 ENCODER mailing list ( http://geek.rcc.se/mp3encoder/ )
