Transmission characteristics of ear canal of artificial head

Abstract

IntroductionThe head related transfer function (HRTF) expresses how the acoustical characteristics change with the sound source position. HRTF is defined as the ratio of the sound pressure at the eardrum to that of the free field at the center of the head [1].If the HRTF is shown as a function on the effect of the pinna, the ear canal, and the body including head and torso, each effect can be discussed separately. If the pinna of an artificial head is removed and/or if the ear canal is blocked, HRTFs can be divided into three parts corresponding to the pinna, the ear canal and the body [2].In this paper, we discuss the impact of the ear canal and how it changes with the sound incidence direction. Measured values are compared with values calculated for a 2-sphere model in which the head and torso are approximated by spheres.