Defend and Protect

Framed against the dry, golden San Diego foothills, the man across the parking lot points a jet-black speaker at me. It looks like a bullhorn — light, even insubstantial. I signal that I’m ready. From the device, his voice booms.

“This is a test of the Long Range Acoustic Device, LRAD. One. Two. Three. Four …”

The voice is shockingly clear, right at my ear and around my head like a helmet. Really, it is in my head. The man in the distance rotates the device to face up toward the sky, and the sound drops off instantly, sucked into a vacuum. He points it back at me, and the voice — “six, seven” — returns.

Then, the siren begins. It is shrill, like a car alarm that has been focused and purified. And loud, louder than anything I have encountered in my life. I raise my hands to shield my ears. Then, abruptly, the device goes silent.

I cross the parking lot. Scott Salas, field service engineer at the LRAD Corporation, is smiling. “I was speaking at room volume,” he says.

The Long Range Acoustic Device is known in defense circles as “acoustic-hailing” technology. By channeling sound waves into precise beams, LRADs can transmit speech and warning tones across great distances — from 500 yards to more than 3 miles — and through vehicles and buildings. The LRAD Corporation, one of the foremost manufacturers of acoustic-hailing tech, supplies tens of millions of dollars’ worth of equipment to military and law-enforcement agencies in more than 70 countries, from Israel to India to the United States. Company brochures portray their machines on battlefields and in civilian settings, defusing hostage crises, guiding people out of active-shooter situations, and warding off terrorists before they attack.

I had driven an hour north of downtown San Diego, through subdivisions and office parks, to reach LRAD’s hillside headquarters. (The company’s next-door neighbor is Northrop Grumman, the defense contractor.) In the lobby, I met Robert Putnam, LRAD’s affable senior marketing manager. He led me through a nondescript cubicle farm to the company’s manufacturing lab. There I saw, in a trailer, a 15-foot-tall pole with a radial, green loudspeaker mounted on top. Putnam explained how search-and-rescue teams on the Midwestern plains use the notification system to warn folks near and far of impending tornadoes.

In the 1990s, LRAD’s founding engineer invented HyperSonic Sound (HSS), a technology in which narrow ultrasound waves of two different frequencies are sent toward a single point; a listener perceives the sound as originating right at the ear’s threshold. He imagined that airports might use HSS to broadcast flight announcements to individual travelers, or museums might use it to communicate with roaming patrons.

Then in October 2000, the USS Cole was bombed off the coast of Yemen. When a boat approached the guided-missile destroyer, sailors had no means of ordering it to keep its distance — and so no way to identify it as a threat. The boat turned out to be carrying al-Qaida insurgents. Navy officials approached LRAD (then called the American Technology Corporation) and tasked its engineers with developing a tool that could help sailors respond to unfamiliar vessels. The result was the Long Range Acoustic Device, which could broadcast a spoken warning and then, if necessary, blast an area with a crowd-dispersing siren.

LRAD’s first success came in 2005 when it helped thwart a Somali pirate attack. Soon, the U.S. Army added the devices to their convoys in Iraq and Afghanistan, installing them on armored vehicles. As they passed through towns, soldiers blared messages through LRADs to clear buildings. At checkpoints, Putnam says, a soldier could command a caravan from more than a mile away to halt without “shooting bullets overhead blindly.” He explains that “LRAD is about clear communication,” which can help avert unnecessary fatalities.

To critics, though, “acoustic hailing” is a euphemism, and companies like LRAD are building “sound cannons,” sonic weapons that are being increasingly deployed off the battlefield. In the past decade, an enormous amount of military-grade hardware has found its way to American police departments — tear gas, assault rifles, flash grenades. In the process, more than 250 departments have acquired acoustic-hailing devices. So has the University of California system, which has purchased at least one LRAD for its campus police.

A couple summers ago, on the night of UCLA’s semiannual “Undie Run,” Clinton Clad-Johnson was jogging through campus in his skivvies when he came across a surreal scene: several other near-naked students scurrying down an alley, covering their ears. As he approached, he saw a line of campus police forming a barrier in front of the runners. A siren rang out. Clad-Johnson pulled out his phone, captured a 30-second snippet of the scene, and posted it to YouTube. A local news outlet picked up the video, identifying the source of the cacophony as an LRAD. Despite pushback from student activists, university police have continued to use the siren on Undie Runners (or, as the liaison between campus cops and the community put it, “to move [them] along and back to where they came from”).

The Undie Run is a decidedly apolitical event, but acoustic-hailing devices have also become a common sight — and sound — at protests. During the Occupy Wall Street demonstrations of 2011, the New York Police Department used an LRAD to broadcast a message to activists. Five years later, police directed an LRAD at people marching through Midtown Manhattan following the death of Eric Garner at the hands of an officer. Earlier this year, a group of protesters sued the NYPD, claiming they were caught within close range of an LRAD and that it was used for “unreasonably long periods.” This past July in Baton Rouge, Louisiana, an armored vehicle with an acoustic-hailing device pushed slowly through a crowd protesting another death, that of Alton Sterling.

Putnam counters activists by listing off common rackets that strike most people as mundane: concerts, fire trucks, ambulances racing by. “If the siren is irritating, you have two hands,” he says, putting his palms to his ears.

These sounds fall in the 120- to 130-decibel range. By contrast, the biggest and loudest LRADs peak at 162 decibels. Rick Friedman, director of the Acoustic Neuroma Center at the University of Southern California, says these volumes can cause serious damage. “There is evolving research on how noise exposure at sub-acoustic-trauma levels damages nerve endings in the cochlea”— the part of the inner ear that sends sound to the brain.

In the future, Putnam envisions LRADs affixed to helicopters to help people trapped in forest and brush fires, and on Coast Guard cutters to patrol shorelines. He describes a massive satellite-like system that can be operated remotely and might someday patrol the U.S.-Mexico border. “You have people who are starving and hungry out there in the desert. How do you communicate to them — live, in their own language, that they can seek help or first aid? How do you tell them where they should go? The LRAD might be an alternative to having a guard every quarter mile. It could save lives.”

Putnam casts his hands from left to right, evoking a line of LRADs watching the border like sentinels. “It’s better than building a wall,” he says.