Can sound go through a wall?

Many complicated things occur when sound reaches a boundary between two different substances. When traveling through the air, it may reflect from a smooth, solid cliff and bounce back with an echo. Part of its energy may be absorbed by a solid wall, which distorts the noise of a loud radio in the next room. How this comes about can be found out from the science of sounds called "acoustics."

Acoustical experts study how sounds are muffled or reflected by various solid substances. Some of their best sound proofers are acoustic tiles. These are riddled with connected oval shaped pores. Until we tone down the racket outdoors, soundproof walls and ceilings are our best defense against noise pollution. However, they are not perfect and some sound gets through, even when the air outdoors is excluded by closed windows and doors.