Kawai Synthesizers

Hi,
today my K1r arrived and I want to use it as a padsynth for my midi bass. Maybe my question 
is very obvious - I tried looking into the manual before to find out by myself but maybe 
somebody here can give me a hint. My midibass send its information on different 
Midichannels - one for each string - so with singlepatches I have the K1r on the receive 
parameter omni. But in a Multipatch I can only tell one sound to watch out for one 
Midichannel - and that way I would have another sound on every string. Is there a way to get 
a Multisound working that each sound reacts to Midichannel 1-3 and so make a real 
Multisound?
Best regards - Christoph