Hey, maybe they have made a miracle with a special firmware, I really dont know how they can compress audio data 12:1 and play by midi.
this is all what I know from this DSP manufacture and drivers.

Just search in google: ATSAM9707 and ATSAM9708
9707= max ram size: 64Mbytes
9708= max ram size :256Mbytes

MAYBE we are totally wrong again...AJ told that thet have used a PC Pentium 4or dualcore with 1Gb RAM or more, remember?
Ask in AJ, for sure he know better.