Вот нашел кое что про ATRAC.Правда там про портатиные плееры, и не факт что все там правда но почитать интересно

"Matsushita (Panasonic) only has two ATRAC versions of their own. The one
seen on SJ-MR100, and the H.D.E.S. version that's now featured on all their
MD recording equipments.

Panasonic players use Sanyo's decoder chip, which Sanyo sold together with a
playback control microcomputer. There has been at least 3 evolutions taking
place since 1997. Sanyo also makes an encode/decode ATRAC DSP for its MD
boombox"

http://www.mail-archive.com/md-l@amulati...10259.html