The background sound level in offices is often so low that voices carry over a distance of 30 to 50 feet (9 to 15 meters), or more. Sound masking systems dramatically reduce that distance. The exact distance is affected by office layout and any other resident acoustic treatments, but 15 to 20 feet (4.5 to 6 meters), or approximately 2 workstations, is a good expectation. It can be less.

Over shorter distances, sound masking may not prevent you hearing that someone is speaking, but it will prevent you from understanding what is being said. This is a key benefit, because understandable speech is the least private and causes the most distraction.