Trust the hardware printing: the Laboratory Experience keyboard is
6VDC,
center positive.
Yes, the manual is misprinted, and yes the Player and Factory keyboards have different voltage inputs due to different regulators. And yes again, all this could be slightly confusing (as I could experience at the Tech Support desk).
@Manuel
@stuey
Folks, please keep in mind that in real life you could (and should) be the best friends in the world, as you are both synth enthusiasts and quite skilled, and I would personally enjoy meeting you two (not as a boxing referee, though). So let's try to keep this place as a gentlemen (and gentlewomen) club.