| ABSORPTION Absorption
of sound is probably the most commonly misunderstood function in acoustics. The
scenario usually goes like this... "I'm trying to keep the noise from
our factory floor from comming through the walls and ceiling of our adjacent office.
I covered the factory side walls with "Sound Proofing" panels and layed
12" of fiberglass across the back of the ceiling tiles in the office. It
made no appreciable difference." Here's why: Acoustic
absorbtion panels are used to reduce the amount of sound that is reflected from
a surface. These panels do very little to decrease the amount of sound that travels
through a structure. The amount of sound that travels through a barrier
or wall is a function of the mass of the barrier or wall. Fiberglass or foam panels
are typically very light (1 to 7 pounds per cubic foot). So, if your wall is made
of wood or metal studs with one layer of 5/8 drywall on each side and insulated
in the cavity, you'd be much better off adding an additional layer of drywall
to each side than adding an absorber. Defintions
| Here's How |