Acoustics is the science that deals with sound. Also called the study of sound properties and control. Sound' is air pressure vibrations propagated through a certain medium (usually air). We hear sound when these vibrations reach the ear. The environment affects these vibrations. The aim is to make vibrations absorb rather than reflect. Hard materials such as stone and glass, for example, reflect sound. The characteristics of a room can therefore make the sound in it disturbing. We try to improve disturbing factors, such as reverberation and echo, with acoustic solutions.