[Five]

Atrac Type R is one possible codec used by MD (right?). MD is "acceptable" when it is the master source, meaning that a minidisc was recorded at a live show either from mics or sbd not from radio and most certainly not after a CDR/DAT/FLAC/whatever.

e.g.

Mics > MD > EMU0404 > Audacity > FLAC = okay

Mics > DAT(m) > MD(0) > CDR(2) > EAC > FLAC = not okay!

so unless your show was actually recorded using minidisc (highly highly doubtful) it is not a good source for trading.