Determination of sound absorption coefficient of wood at different thickness as a function of frequency

Abstract

This experiment has been designed to determine the sound absorption coefficient, α of wood sample of thickness 0.2 and 0.6 inches at different frequencies. The α of thin and thick plywoods at frequencies 660-1,000 Hz are within 0.90-0.98 and 0.82-0.90, respectively. The α of the wooden sample depends on the frequency of sound wave and sample thickness. The frequency range for which each wood slab has reached the maximum absorption coefficient α_max (>0.90) was likewise determined. The thinner sample attained its α_max at lower frequencies (660-
1,000Hz) while α is maximum at higher range of frequencies (1,000-2,000Hz) for the thicker sample.