A Study on Acoustical Characteristics of Ear Canal by Earphones (A Derivation of Resonance Correction Filter by Using Transfer Matrix Method)

Abstract

This paper attempts to improve the performance of ear-plug type earphones. The transmission characteristics of the ear canal with/without earphones are different. Therefore, the sound quality of the earphone is a little poor compared with audio speaker. In addition, it is well-known that the acoustical characteristics of ear canal vary among individuals. Therefore, we are studying to predict the acoustical characteristics of ear canal with ear-plug type earphones by using transfer matrix method and are studying how to improve the transmission characteristics of the ear canal. In this paper, a method for adjusting the resonance characteristic of the ear canal with earphones to the characteristic of the ear canal of AV speakers without earphones using digital filtering technique is proposed. With this method, the improvement of the sound reproduction performance was verified on the basis of experiments.