With noise we understand that all the adjacent surfaces do not correctly reflect the speech or music.
Acoustics show how sound reacts in a room. If the room does not have any sound absorbing surfaces, sound will “bounce” off surfaces making it become louder and taking it a long time until the sound disappears. For the listener in such an area, it is difficult to perceive the speaker because the person hears both the direct sound and repeated reflected sound waves or echo.
People with prolonged overstrain on hearing will have an affected central nervous system – they will experience fatigue, insomnia, reduced concentration and performance.