Acoustics can be de“ned as the generation, transmission, and reception of energy in the form of vibrational waves in matter. As the atoms or molecules of a ™uid or sound are moved from their normal con“gurations, restorative elastic force arises. The elastic restoring force, coupled with the inertia of the system, allows the material to participate in oscillatory vibrations and consequently generate and transmit acoustic waves. Acoustics cover a wide range of scienti“c and engineering disciplines (Recuero López, 2000).