Acoustic impedance measurements with a sound intensity meter

Abstract

Acoustic impedance measurements have been made by evaluating, with a sound intensity meter, sound pressure and normal velocity close to absorbing material samples. Measurements have been made both in a Kundt interferometer and in the free field. With the Kundt interferometer the same results are achieved as with the classical Kundt interferometer but the present method is much faster and easier to implement. Free field measurements are accurate for frequencies high enough to allow one to neglect the finite dimension effect of the absorbing material sample.