bohan wrote:
H9 doesn’t support custom scales. However, you may use an expression pedal or a MIDI controller to change the Pitch/scale parameters in real time while playing.
Thank you very much, @bohan
I had feared that.
It is a pity, because to use a pedal to change the parameter in just the right moment, is too much to do (and to think) for an old man, when he is playing with the band. 
Best wishes! 
