Short for MPEG Audio Decoder, MAD is an MPEG audio decoder that has a reputation for excellent sound quality. MAD is fully compliant, having satisfied the ISO/IEC 11172-4 computational accuracy requirements for compliance and so qualifies (in most conditions) as a Full Layer III ISO/IEC 11172-3 audio decoder as defined by the standard. Currently supports MPEG-1, MPEG-2 Lower Sampling Frequencies extension and "MPEG 2.5". All three audio layers (Layer I, Layer II and Layer III) are fully implemented. MAD does not yet support MPEG-2 multichannel audio (though it should be backwardly compatible with those streams) or Advanced Audio Coding (AAC).

Some of MAD's features include:

  • 24-bit PCM output, which allows high quality audio
  • 100% fixed point (integer) computation, which makes it suited for environments without a floating point unit
  • brand new implementation based on the ISO/IEC standards
  • distributed under the terms of the GNU General Public License (GPL)

    Based on inital listenings with this decoder, the sound quality appears to be very good although higher quality equipment would help as well as any listening tests.

MAD appears to be quite widely implemented, as the following list of programs containing MAD will show:

MAD homepage -