When you’re trying to build apartments where neighbors can have privacy from one another, classrooms where the instructor can be heard without taxing their voice, or a sound booth for the recording of an audiobook, you take into account the materials and design that will treat sound and noise for your needs. The goal is better sound and less noise.

Sound travels in waves that emit from a source. How far the waves travel depends on their intensity starting out and what they bump into. If the sound waves are in the air, then they’ll travel freely. If they hit water, they won’t go much further, because the water absorbs the sound wave.

Sound waves bounce off of some surfaces, particularly those that are hard, smooth, and made of a dense material. These include things like marble, polished stone, and tiles; the kind of surfaces you find in the lobbies of big government buildings and museums. Places like these are great spots for creating echoes, but if there are a lot of people around, and everyone is talking, it can get very noisy. Situations like these can make it extremely difficult to understand the person you’re having a conversation with, for two reasons: 1. because your ears and brain are getting multiple bouncing sound waves at once, and 2. speech is a series of different sounds, produced in rapid succession.

Given what we know about how sound moves, there are several things we can do to optimize the environment for speech:

·       Builders can select construction materials that won’t help sound continue to travel.

·       Use carpeting and rugs to dampen sound waves in the environment

·       Hang acoustic panels or cloth decorations (such as tapestries) on the walls to attenuate sound and reduce echo

·       Set up furniture in reasonable proximity for a conversation. It is a lot harder to have a conversation across a room than when you are sitting next to the person.

·       Earthen embankments and other strategic landscaping can reduce the sounds from traffic and other outside sources that may enter a room.

The next time you’re having difficulty hearing someone, take a look around and take a moment to identify potential reasons. Then, if there is something you can do about your situation to improve the acoustics, take action. Once you can hear the other person and they can hear you, let them hear your ideas.