To my understanding, Cubase Pro 9 is a 64-bit application only. I have a Yamaha Motif XS6 that I purchased back in 2008 that still play awesome midi sounds. Would I still be able to transfer/play midi on the Cubase Pro 9 using USB to Host transfer from my keyboard?
Or do I have to buy a modern keyboard synthesizer and now my keyboard is useless.
Provided you have a MIDI interface that can talk to the Motif, it should work just fine within Cubase. The 64-bit is for plug-ins, but a physical MIDI keyboard or Rack unit controlled by a MIDI keyboard controller should be fine. Good luck.