Device Gives Police Sirens Some Backup

Vienna Officer W.G. Murray demonstrates the Rumbler, which augments sirens with an amplifier and subwoofers.
Vienna Officer W.G. Murray demonstrates the Rumbler, which augments sirens with an amplifier and subwoofers. (By Tom Jackman -- The Washington Post)
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By Tom Jackman
Washington Post Staff Writer
Thursday, May 8, 2008

The town of Vienna isn't big, but anyone who's tried to navigate its main streets at peak times knows it can be crowded and noisy. And that can hamper a police cruiser trying to get somewhere quickly.

Enter the Rumbler.

Vienna police are testing the Rumbler, a device that augments the standard siren with an amplifier and two subwoofers, creating a lower-pitched sound that should cut through virtually any traffic din and that can create vibrations that might get the attention of otherwise soundproofed motorists or pedestrians.

The police hope that drivers or walkers "will start looking around, and hopefully they'll find the emergency vehicle" and clear the way, said Officer W.G. Murray of the Vienna Police Department. Vienna, which has 11 patrol cars to cover its 4.4 square miles, will rotate officers into the single car outfitted with the Rumbler, to give most officers a chance to gauge its effectiveness.

The Rumbler consists of two speakers, mounted inside the front bumper, that emit a lower-pitched siren that seems to slice through ambient noise more effectively. The device even creates a small but noticeable vibration inside a car, much like when a passing car is playing a thunderous hip-hop song. Police, fire and ambulance drivers often express frustration when traffic doesn't clear for an emergency vehicle, and the situation can be potentially fatal if cars unknowingly drive across the path of a speeding firetruck or police car.

"I had times, when I was in patrol, where I knew people didn't hear" the siren, said Vienna Detective James K. Sheeran as he watched the Rumbler being demonstrated. "I know they didn't hear it, because they didn't know why I walked up to their cars" when they did pull over, Sheeran said.

The Rumbler is only about two years old, but it has been picked up by about 200 police and sheriff's agencies throughout the country, according to its manufacturer, Federal Signal Corp. of Oak Brook, Ill. D.C. police equipped about four dozen cars with the Rumbler in the fall and plan to expand it to all 767 of the department's marked patrol cars.

Police or sheriff's departments in Maryland's Calvert, Charles and Howard counties are also using it, said Tom Morgan, a vice president for Federal Signal.

"It started really being accepted much faster on the East Coast," Morgan said. "Which makes sense because those are the densest metropolitan areas; I think that's where people see the greatest effect." The Rumbler is being tested by New York police, too.

"People are cocooning themselves in their cars," Morgan said. "We all do it, with iPods, stereos, the air conditioning. That lower frequency comes rumbling in, and some people have described it as obnoxious. The police officers see that as a plus."

At a cost of about $350 per unit, "it's definitely not cost-prohibitive," Murray, of the Vienna police, said. "If the officers find it helps them do their jobs better, or prevents even one person from getting involved in a police-related crash, we'll have to look at getting some more of them."

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