root bass and chord can be accessed in the mixer or in part setting:
Press Program Menus.
Press Sound in the screen.
Two choices:
Press Part Setting, then at top right of screen scroll along the parts till right at the end you get to R.BASS and CHORD.
In the screen you can take the volume box down to 0.
Other choice:
Press Mixer.
Press Other Parts/Tr button under the screen bottom left twice.
The sliders will include a R.BA and CHRD, zero these.
Incidentally you can change the voices just like the other parts if that is what you want.

you can save this in a panel memory as normal but it is more intelligent to save a personal starting registration in the custom panel:

Press Customise.
Press Custom Panel Mode in the screen.
Choose All Panel.
Press OK in the screen.
Exit out and save your setup in the same way you save panel memories by holding the middle SET button and pressing the Custom Panel button instead of a numbered button.

Now every time you switch on the keyboard press the Custom button. The root bass and chord sounds will be gone and you can save any other personal preferences like footswitch settings, split points, key sensitivities etc etc etc which will then be saved in any panel memories you save from then on without having to re-create each setting. This is just faster than loading a personal start up file, even from SD card. There are also filters to prevent your personal settings being changed when loading someone else's files but that is another story

Hi Technicsplayer, I am very grateful to you for going into such detail regarding this. That is exactly the result I wanted. Is there somewhere on the web where there is tutorials on the KN7000? Many thanks, Jess