My air calliope project is moving forward.  I have the brass tubing and
a blower unit and have been making pipe bases from UHMW polyethylene.
I will get a John Wale MIDI board and a keyboard.

I know most calliopes are 43-note.  Why is that?  How much would I be
giving up by making a 20 to 25-note calliope?  A smaller, lighter unit
would have mobility advantages.  What notes should I include?

Can you tell I'm new at this? Thanks for your help.

Bruce Brockett