Source : Free On-Line Dictionary of Computing

transparent audio coding
     
         A {lossy audio compression} {algorithm}
        is transparent if the original and decoded signal are
        indistinguishable to the human ear.  The bit rate depends on
        the {codec} and the audio material.  Some codecs (e.g. {AAC},
        {MP3}) are optimized for transparent coding at a low data
        rate, others (e.g. {VQF}, {MP3Pro}, {AAC}+{SBR}, {WMA}) for
        distinguisable but pleasant reproduction at lower bit rates.
     
        Typical data rates in {kbps} for different codecs are:
     
         MP1         288-320
         MP2         224-256
         MP3         160-224
         MPEG-2 AAC  128-160
         MPEG-4 AAC  112-144
         MPEGplus    160-200
     
        (2001-12-23)