The video link is a good one. I've been dabbling with the Duo and not all the note combinations work well. And high D will require both hands on the main, 6 hole whistle and the melody whistle does not harmonize with it, I'm surprised Susato does not have a print or video tutorial. They have not responded to an email inquiry, which admittedly has only been a week or so. Still the whistle has potential. I just need to press on with it.
I too have a double ocarina from Charlie Hind. It is handcrafted, high end and just sits about unused.
updated by @michael-w6: 03/09/21 04:45:09PM