Determination of Sabine Coefficient from Acoustic Impedance Measurement and Its Application in Studio Design

ABSTRACT

Values of absorption coefficient α₀ and α_s for normal and random incidence of sound respectively have been derived from the measured acoustic impedance of sound absorbing materials. It has been found that α₀ is maximum and greater than α_s only when a material has specific acoustic impedance | (or mid);Z| (or mid);/ρ C < 1, otherwise α_s is always greater than α₀. The values of α₀ and α_s, so measured, have been compared with the values of absorption coefficient α, derived from reverberation measurements in the studios. It has been found that when random sound field exists in a studio, α_s is same as α, otherwise its value lies between α₀ and α_s depending upon the conditions of sound diffusion inside the studio.