mp1

from The Free On-line Dictionary of Computing (8 July 2008)

MPEG-1 audio layer 1
MP1

   <audio, compression, algorithm> (MP1) A simple 32-{subband}
   {audio compressor} using a {floating point} representation for
   subband samples.  Resolution and scale factor are stored for
   groups of 12 subsamples.  MP1 is only used for {Philips} DCC
   {Digital Compact cassette} with data rates of 384 kbps.

   (2001-12-02)