MIMF

Clay Schaeffer has just reminded me of a didge I saw in Kuranda, Qld ,Australia which was circular. In effect it was a tube that had been routed into a square of timber(two halves glued together). The bore was conical. Ideal for travelling.

I have not seen joints with O rings but you could use telescoping brass tube. The only break down didges I have seen were made from plastic irrigation stand pipes where one size slides into another. They lock together with a threaded taper lock. This also makes them 'tuneable'.

I am wishing to make an Ocarina out of a beer bottle. Does anyone have a formula for calculating the size of the windway and labium for any given chamber volume?