A Study on the Acoustical Characteristics of the Absorbent Materials Using Two Microphones

두개의 마이크로폰을 이용한 흡음재의 음향특성 조사

  • 정성수 (한국표준과학연구원, 음향진동그룹) ;
  • 황철호 (한국표준과학연구원, 음향진동그룹)
  • Published : 1996.04.01

Abstract

A free field method using two microphones is used for measuring surface impedance and absorption coefficient of the absorbent materials. It is shown that this method can be performed in a large non-anechoic room. Precise values of the surface impedance can be obtained by changing the spaces between the two microphones. Comparison between experimental values of the surface impedance of the glass wool and the mineral wool and Miki's empirical model shows agreement.

Keywords

References

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