On 11th May 2023 Dr Haydar Aygun  gave a talk at the Institute of Acoustics (IOA) May 2023 London Branch held at London South Bank University.  The talk was delivered in person and simultaneously streamed online to a remote audience. Haydar’s talk was entitled Acoustic wave propagation through natural and conventional porous materials and covered his past and present research work around vibration, sound radiation, and acoustic attenuation mechanism of sound absorbing materials.