Physics-based model of the sound generation by dynamic lingual organ pipes

Dynamic lingual organ pipes utilize a blown open free tongue which allows for changing the loudness of the pipe by the blowing pressure with maintaining a steady pitch. This principle is in contrast with traditional reed pipes that have blown closed tongues and always operate at a specified windchest pressure. A physics-based model of the sound generation by the dynamic lingual pipe construction is elaborated in this paper and the design parameters affecting the pipe sound are explored. The physical model incorporates a modal description of the vibration of the tongue, a one-dimensional waveguide model of the resonator, and a flow model for the coupling of the tongue and the resonator.First, the effects of tuning the tongue and the resonator are discussed whereby different domains of operation are discovered. Then, a sensitivity analysis is performed to determine the most important parameters for sound design. The examined parameters include the curvature of the tongue, the gap size on the tongue holder plate, and the position of the tongue along the length of the resonator. As a validation of the model, comparisons with measurements on experimental pipes are presented.