When I was a kid, the best way to get my brothers to stop talking was to repeat what they said right after they said it. Now, the U.S. Navy has taken that simple concept and expanded upon it to disrupt people from speaking at a distance. Their invention, known as the handheld acoustic hailing and disruption (AHAD) system, captures speech using a long-range microphone, then plays it back after a brief delay. Not only is the result annoying to its target, but there is also scientific evidence that playing back one’s speech immediately after speaking can quickly disrupt our ability to speak coherently.
The AHAD system was invented by Christopher A. Brown of the Naval Surface Warfare Center – Crane Division, and the Patent abstract below explains how it works:
“The present invention relates to a communication disruption system. In a first audio path, a microphone receives input sound, an amplifier system amplifies the sound, and a sound system transmits a first output sound. In a second audio path, the microphone receives input sound, a delay circuit delays the sound, the amplifier system amplifies the sound, and the sound system transmits a second output sound. A target speaker will hear the first and second output sounds, with the first output sound being a reproduction of their speech heard nearly simultaneously with the original speech, and the second output sound being a reproduction of their speech heard slightly after the original speech. Due to the delayed auditory feedback effect, the target speaker’s concentration will be disrupted, making it difficult for them to continue speaking.”
While the Navy could use such a device to prevent terrorists from communicating or disrupting military activity, I could also see this tech being used for nefarious purposes, like preventing free speech at protests. On the other hand, I’d love a personal version of this that I could use during boring PowerPoint presentations.
[via Popular Mechanics]