Room Treatment and Acoustics

Using Room Treatment To Your Advantage

I will assume you don’t have a dedicated listening room, or the ideal room dimensions. Don’t worry, most people don’t. How do you minimize the bad surface reflections and tame the bass?

You can use room treatment, which is usually divided into two categories: Absorbers and diffusers.

Absorbers are used to absorb the sound energy as it reaches a surface, so it does not reflect. In small rooms, absorbers are very effective at reducing reverberations and flattening out peaks and dips in the frequency response. Absorbers come in a variety of materials and designs, but they are usually sold as either acoustic foam or acoustic panels. Acoustic foam comes in different thicknesses and surface patterns that have different effects on the sound and are designed to handle different frequencies. Acoustic panels are also highly effective and are usually wooden frames encasing an absorptive material such as mineral wool. One major upside of acoustic panels is that they look like picture frames that integrate better in the home environment. I don’t blame anyone for not wanting a bunch of acoustic foam in their living room.

Bass traps are another kind of absorber. They can be used to tame a broader range of bass frequencies, or be tuned to a specific frequency to solve an issue at that particular frequency. Bass traps are most commonly used at the corners of the room to minimize energy buildup. The major downside of using these is that they take up more space than a wall panel would.

Diffusers disperse the incoming sound, which can help to minimize localized reflections that reveal the boundaries of the room when they hit the listener’s ear. Diffusors come in many different shapes and sizes and are designed specifically to create even dispersion across a certain frequency range. In small rooms, using diffusors can be tricky because if they too close to the listener, there is not enough space for the sound waves to spread out leading to the impression that the diffusor is actually creating resonances of its own. In addition, a diffusor cannot make up for other reflective issues in the room. Other reflections that cause peaks and dips will still be present, but the diffusor may make it so it isn’t as localizable to a specific problem area.

Diffusors, like absorbers, are tools that only lead to a favorable outcome when placed properly and used in the appropriate circumstances. Simply placing random treatment around the room will not automatically make it sound better. It could even make it sound much worse. By understanding what the different types of room treatment are used for, you can make a more informed decision on what might be best to purchase and implement for your specific room. Usually, a combination of absorption and diffusion leads to the best results.