In an experimental setup, the acoustic properties of porous absorbers are measured using an impedance tube, commonly referred to as Kundt’s tube. Within the impedance tube, a plane sound wave is generated and directed towards a sound-absorbing specimen in front of a reverberant termination. The sound pressure resulting from this is measured by two microphones positioned in front of the material sample. By evaluating the incoming and reflected sound energy at the desired sound frequency values, the sound absorption coefficient of the material is determined.