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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.

Step 4: Build a Better Wall
A typical 2 x 4 wood-stud wall with fiberglass insulation has an STC rating of 38. But a quiet media room requires special construction techniques. Double-stacking 0.625-inch drywall on both sides of a 2 x 4 wall increases the STC rating to 43 to 45, while staggered-stud construction increases the rating to 46 or 47. A double wall with an air gap in between produces a rating of 56 to 59. "Floating" the sheetrock on a resilient channel can dramatically decrease sound transmission. Also, installing dense acoustic matting material such as Acoustiblok beneath the sheetrock can give a standard 2 x 4 wall a rating of 52. Quiet Solutions' QuietRock claims an STC rating up to 80 and meets THX's certification for sound isolation.

Step 5: Windows and Doors
Windows let in light, are highly reflective, and provide another way for sound to get in and out. If you must have windows, seek out specially constructed ones designed with sound treatment in mind. Your room needs to have a door, but buying the right one will make all the difference. Select one with solid-core construction that sits in a specially designed frame and threshold that seals sound in. For the ultimate in sound control, build a dual-door system — like an airlock — that can keep nearly all sound from escaping through the door.

Step 6: Minimize Penetrations
If there are any cracks or gaps in your walls, sound will leak through them. Any penetrations in the walls or ceiling such as recessed lights, HVAC registers, or electrical outlets also create pathways for sound to escape. Make sure any penetrations are properly sealed. In-wall/ceiling speakers need to be installed in specially designed acoustic enclosures that not only improve their performance but keep sound from blasting into other areas. If the theater shares a wall with another room, make sure there aren't penetrations on both sides in shared stud bays.

Step 7: After Construction
Once the walls for your theater are built, your sound-treatment options are more limited. Thick padding and carpeting can help to soak up sounds, and sound-deadening mats underneath the flooring are especially helpful for keeping sound from leaking into any rooms below. Thick drapes will also absorb some sounds, but mainly in the mid to upper frequencies. There's only one real cure for boomy bass heard in other rooms: Lower the volume.

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