The Sound Gun That Will Leave You Speechless

A new device uses an auditory phenomenon to silence people remotely

The prototype SpeechJammer gun, created by Japanese researchers.
The prototype SpeechJammer gun, created by Japanese researchers. Feedloader (Clickability)

For those who have suffered sitting next to bad mannered talkers at movie theaters or endured distracting chatter at the library, a pair of researchers from Japan’s National Institute of Advanced Industrial Science and Technology and Ochanomizu University have the device for you: the SpeechJammer. A paper published last week by Kazutaka Kurihara and Koji Tsukada detailed the unusual invention, seemingly from the realm of science fiction. If silence is golden, the SpeechJammer is a modern-day Midas.

The SpeechJammer prototype can “jam” the voices of speakers as far as 100 feet away by using a phenomenon we know well from phone calls with an echo. When the gun’s user pulls the trigger, a sensitive directional microphone records the speech of the target, and a powerful directional speaker projects it right back at the target, fractions of a second later. Because it’s virtually impossible to talk when we’re hearing our own delayed words—a principle known as Delayed Auditory Feedback—the gun effectively leaves the target speechless.

The device’s capacity to jam speech was confirmed in a preliminary study with five participants. The researchers extol the device’s ability to precisely silence a single speaker from a distance, without causing any pain. “The system can disturb remote people’s speech without any physical discomfort,” they wrote. “Furthermore, this effect does not involve anyone but the speaker.”

Potential applications for the device are varied; the researchers suggest it could be used to enforce silence in settings like public libraries and trains, and moderate formal discussions or debates. ”Some people tend to lengthen their turns or deliberately interrupt other people when it is their turn in order to establish their presence rather than achieve more fruitful discussions,” the paper notes. At future political debates, perhaps, the SpeechJammer could be aimed at candidates who attempt to talk past the buzzer.

But across the blogosphere, writers have dreamed up other possible uses that are stranger, and perhaps a little unsettling. ”There are still many cases in which the negative aspects of speech become a barrier to the peaceful resolution of conflicts, sometimes further harming society,” the researchers argue. Could audience members be remotely silenced by arrays of SpeechJammers? Could crowds of protestors at a political rally be rendered silent at will?

The effectiveness of the SpeechJammer has one exception, though: In the study, speakers were still able to emit meaningless sound sequences such as “ahhhh” when subject to the weapon. If nothing else, this will enable crowds of upset, silenced people to show their displeasure—by saying “booooooo.”

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