Step By Step: How to Soundproof Your Home Theater

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Even if you live alone in the woods, there are still reasons why you'd want to treat your room for sound. By making your listening environment quieter, you'll improve your system's dynamic range and create a more immersive experience. For those of us who don't live alone in the woods, sound treatments let us listen to movies and music louder without disturbing the rest of the house. Whatever your reasons, following these seven steps will help quiet things down!

Step 1: Know the Numbers Fortunately, sound acts in predictable ways, traveling through air at 1,130 feet per second and decaying by 6 decibels (dB) every time it doubles in distance. For instance, sound that measures 100 dB at 1 meter from your speaker will be 94 dB at 2 meters away, 88 dB at 4 meters away, and so on. We also know that we perceive a 10 dB difference in level to be about one-half or twice as loud.

Step 2: Determine the STC Rating You can't talk about sound treatment without talking about STC (Sound Transmission Class) ratings, which describe a material's ability to affect sound transfer at frequencies between 125 and 4,000 Hz. The higher the rating, the more noise is blocked. STC ratings depend heavily on the wall's construction, and a material or wall's rating can be increased by adding mass, increasing air space, or adding absorptive material. A wall with an STC rating of 35 to 37 allows medium-loud speech to be heard on the other side. At 50 to 52, loud speech is inaudible, but deep bass can still be heard. A rating greater 65 means most airborne noise is blocked.

Step 3: Select the Right Location Building a quiet room isn't cheap, and selecting the right place for your theater can save you thousands of dollars in treatments. Use a room that can be closed off from the rest of the house. And try to find a location away from areas that produce lots of noise or that require extra quiet: bedrooms, a home office, the nursery, and so on. Seldom-used spaces such as dining rooms, bathrooms, gyms, or hallways are ideal for buffering the theater from the rest of the house. Equipment such as pool pumps and heating/cooling systems produces not only airborne noise, but mechanical noise that's harder to eliminate.