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Archive for the ‘Audio’ Category

Taking the Garage Band Underground

Thursday, November 26, 2009@ 4:44 PM
Author: Frank Stevens

Taking the Garage Band Underground

The term garage band comes from the fact that many teens form musical bands and their parents can’t stand the noise in the house. So they are relegated to the garage where the distance and the walls help reduce some of the noise at least. There’s also usually more room in the garage to leave the instruments and equipment set-up if the band members can talk the home-owners into parking their vehicles outside for the foreseeable future. While the garage may be the first choice to give the band the space they need while cutting down on noise, there are other options.

The garage simply moves the noise to another location. The flimsy garage door and lightly insulated walls barely contain the sounds and instead of the primary homeowners being exposed to too much noise, now the entire neighborhood gets an earful whether they want to or not. Using the basement instead can help prevent starting a war with the neighbors over noise. The basement has the advantage of thick cement walls buried in the ground to help smother the sounds before they leak out. The ceiling, however, can be a problem. The bass drum can seem like it’s shaking the whole house, and the muffled higher frequencies can make normal conversation all but impossible on the first floor of the home while the band is practicing.

This problem can be mitigated with the use of acoustic insulation. Acoustic insulation is simply material that absorbs and dampens sound waves as they pass through it. Some people just stuff copious volumes of fiberglass into the basement ceiling, and that certainly helps. The best acoustic insulation, however, will have layers of materials with different densities. It is the transition between these layers where much of the sound reduction occurs. Sound waves are simply alternating waves of higher pressure and lower pressure. The transfer of these pressure waves from one material into another is a fairly inefficient process and much of the energy is lost along these boundaries, especially if the right materials are chosen to maximize this effect.

Layers of rigid fiberglass panels sandwiching loosely packed batting or foam insulation works very well to reduce the amount of sound that leaks through. These kinds of acoustic treatments can actually work in any room, but if the basement is used, it reduces the area that needs to be covered, since the cement and surrounding dirt will be effectively insulating most of the space.

Using the basement and applying some acoustic insulation to the room frees up the garage for the cars and lawnmower for which it was intended. Of course, instead of a garage band, fans might have to refer to them as an underground band.