I have lengthened the airway on my low D whistles, which has improved them. They have a more focused tone now and more volume. Here is a photo, showing the longer beak.
While I have your attention, I’ll show you what’s happening in the wooden whistle department at O’Brien Whistles. Here you can see an African blackwood set of Rovers in D, C and Eb, that is just about ready to send off.
And a set of rosewood Rovers, still waiting for some more brass, holes and tung oil:
