Thanks Ian, the big Tannoy Autographs are such a grand sound and down to the design of the driver ultimately, there will be more to come there as we move forward with various plans. I am worried I am biting off more than I can chew as a novice to CNC but was hoping to take on these horns myself if at all possible, the throat is 3.81mm in diameter to suit the compression drive unit ajoining it. Obviously I cannot expect .1mm degree accuracy but was hoping have a dedicated machine for say 5 horns with a small amount of finishing involved.