DOC is a registered trademark of Yamaha. These files are also supposed to be compatible with my PR902 in 'Direct Play' mode, although I have been unable to find a sales outlet for them. PianoDisc is a registered trademark of Music System Research. PianoDisc makes units that are installed on conventional pianos - it turns them into 'player piano's'. I've seen these units in various settings - on an unattended piano playing in a hotel lobby, for example. These disks are supposed to be compatible with the KN6500 and the PRx02, and PRx03 series of Digital Ensembles as well as the new PR1000. I just haven't seen any posts anywhere from anyone who has used them on the Technics. They supposedly work only in 'Direct Play' mode. That is about all I can gather from my PR902 user manual and the product brochures for the instruments mentioned. Interestingly, the KN6000 does not list compatibility with the PianoDisc files. The PianoDisc site does not guarantee compatibility with any 3rd party equipment other than their own device.

Rob