dlstarry ... I had the same unit ... the technician I used to bring it to (about every other week!) said one of the problems was that the 'tuning pots' for each note were too delicate to be in the amp unit, especially since the bass went through there as well ... I still have mine stored somewhere in the basement ... putting that box in the trunk of a car (big assed '75 olds) was no fun ... and then I went to the Fender Rhodes stage model!!!
I'm not familiar with the 9000, but am personally having a lot of fun with the kn6000.
t.