Eric, what do you mean by the same keybed as the accordion? Do you mean a heavier action? Otherwise, I can’t see too much difference in the keyboard?
As MM says, 2 reeded melodicas have already been made – I have a couple of Vibrandoneons with 2 sets of accordion style reeds. I actually prefer a more standard melodica to them, as they’re easier to play.
I also think we should be looking at technique – the melodica is unique, and has many advantages over its free reed cousins because of the wind control, and the light reeds which enable so much expression.
How do you envisage your ideal instrument? And how would you describe the potential musical advantages? How would it be different from the Vibrandoneon or similar models?