Parker, The mouth piece is longer than usual for a couple of reasons. I tapered it from each end with some restriction in the middle, thinking it should increase the velocity of the air crossing the hole of the resonant cavity,increasing the fundamental amplitude (acoustic intensity) of the instrument, also effectively reducing the amount of air required to operate it. Other factors of course are the bore diameter, length, and size of the hole, all of which dictate the tone and volume of the call.