Acoustic wall panels are an inexpensive and effective way to improve the acoustics of a room used for music recording, rehearsal, and home theaters. Acoustic panels are also often used in offices, schools, clubs and even restaurants, where controlling reverberation (echoing sounds) improves the intelligibility of speech and music.
By building the acoustic panels yourself, you'll save at least half the cost of purchasing finished panels, with no difference in quality. The standard size for acoustic panels is 24-by-48 inches. You can, of course, adapt the design and build custom panel sizes suited to your needs.
Calculate how many panels you need for your room. For optimal acoustic treatment, calculate one panel for every four feet of wall length. Calculate one additional panel for each corner. In offices or restaurants, you may have to use fewer panels due to space limitations. In this case, mount a panel on one of two parallel walls to treat common "flutter echo" acoustic problems.
Purchase most materials from a hardware store, which will carry lumber, wood glue, staple guns and staples. You may have to search the Internet for an online supplier of Owens-Corning 703 insulation. Purchase 24-by-48-inch Owens-Corning 703 insulation panels of 4-inch thickness. One panel will yield one acoustic wall panel.
Purchase fabric for covering the panels from any store carrying housewares or craft supplies. Pick a fabric that you like to cover the absorbers, and buy 3 yards per panel. The material is not important for the function of the absorber, it only serves to hold in the insulation and to make the absorbers look good.
Cut the lumber for building frames so that the boards for the short sides overlap the boards for the long sides. Cut two 48 inch lengths and two 31 inch lengths from the 1-by-4 lumber for each acoustic panel. At larger hardware stores, you can purchase the wood pre-cut; this saves you time, the cost of a saw and the cleanup afterward.
Lay one 48-inch piece of lumber on the floor, standing horizontally on the 1 inch edge, and apply wood glue to the end on the 4-inch side. Butt a 31-inch board at a right angle, keeping the outside edge flush to the 48-inch board. Press the 31-inch board into the glue and staple along the outside edges to secure it.
Join another 48-inch board to the other end of the 31-inch board by gluing and stapling in the same manner. Close the rectangle with a second 31-inch board.
Allow the frame to dry overnight. If you want to complete the project in one day, you can carefully handle the frame after allowing the glue to dry for two to three hours.
Unpack the insulation in a well-ventilated garage or workroom. Place the acoustic insulation into the wood frames.
Spread out enough fabric to completely wrap the frame and insulation on both sides. Write down the length of fabric you use for reference when assembling further acoustic panels. Wrap the frame as if it were a big Christmas present. The fabric will hold the insulation into the frame.
Staple the fabric along the back side of the panel, along the 1-inch edge of the wood frame. Use one staple every 6 inches, and alternate stapling the left and right sides to keep mild tension on the fabric. Fold the corners of the fabric onto the wood frame and secure them with two or three staples. Thicker fabric may require more staples.
Mount the acoustic panels to the walls in your room as you would mount a large picture frame. To combat the buildup of bass frequencies in corners, place an additional panel across the corner of a room at 45 degrees to each wall.
In Europe, Rockwool "Sonorock" is the preferable insulation material for acoustic panels. It is generally available in 100 cm-by-62.5 cm panels in various thickness: 10 cm thick Rockwool is a good choice, since 10 cm wide lumber is widely available for building the frames.
Acoustic panels can also be used to display artwork or photos, making the panels less obtrusive in offices, clubs and restaurants. This will not adversely affect the sound absorbing properties.
Choose lumber that is not warped. Curves in the frames make it difficult to lay in the insulation.
Don't use nails or screws when building the frames; they may split to wood.
Don't use the relatively low-density pink fiberglass insulation found in most hardware stores. It has insufficient acoustic absorption properties for acoustic panels.
Wear gloves, long sleeves, a dust mask and protective goggles when handling insulation.