By: Daniel Dick
In the studio, in any live performance, basically anywhere music is being played, how the music sounds is the most important thing. Sure, the way they artists are dressed might be cool to see, and sure, the way they strut around stage might grab your attention, but the way they sound is definitely the most important component of the performance or recording. Part of the sound that they produce that is so essential to artists is the noise barrier that they use to reflect or absorb the sound waves. Different barriers cause different effects on the sound waves. There are five different and sound barriers that can alter the behavior of the sound wave: absorption, reflection, noise cancelation, room within a room, and diffusion.
Absorption is caused by a soft surface being struck by the sound wave. The ability of an object absorbing the sound wave is based on five different factors: Cell size, Tortuosity, Porosity, Material Thickness, and Material Density. What is meant by Cell size is the dimensions of the object. Tortuosity means the twistedness of the shape. Porosity means the size of the pores and how many of them are present in the material. The material thickness and material density are self-explanatory in the name. Recording artists use a room full of sound-absorbing objects to make sure the sound waves don’t bounce off the walls. This gives a nice direct sound in the recording.
The other sound barrier used to alter the behavior of the sound wave is reflection. Reflection of a sound wave is caused by an object that gets struck with a sound wave, and then bounces it back. The object has to meet certain requirements to reflect sound. It has to be solid, non-porous, and very dense. Ceramic tiles, marble, and basically anything else that you would use for your bathroom are classified as reflecting material. Once the sound wave hits the object, it travels in the opposite direction.
One other sound barrier...