Tony its hard to explain & so long ago, but I remember compared to my KN5000 the 6k was a bit difficult to set up for my needs the way I like it too sound....so I returned the 6k & 65k withing weeks of purchase......I test drove a 7k at Dan O's store and the sunken keybed was terrible because both ends are sunk down and walled restricting my fingers high & low....The giant tilt up display is like the starship enterprise not natural for my playing style at all, difficult to access features buttons on the fly in split second changes,....I did however love the speaker system. I dumped them all and remember buying two Yamaha Psr9000 ...to each his own.