Passive Control of Radiation Directivity for Auditory Signals

Abstract

This paper describes a study on control of radiation directivity for auditory signals. A model analyzed here consists of a primary point source and one or more passive point sources when the primary source radiates a pure tone with a constant volume velocity. The passive sources respond acoustically to the applied sound pressure radiated from the primary source in same frequency. The relation between the volume velocities of the passive sources without any limitation and directivity is analitically obtained first. The limitation on the amplitudes and phases are taken into consideration next. The effects of the acoustic impedance on the directivity in case of the single passive source are discussed in detail.