The Rumbler is a response to new vehicle models with better aural insulation, louder car stereos, and the increased prevalence of iPod and cell phone use among drivers. In this environment, high-pitched sirens are decreasingly effective at alerting drivers to the presence of emergency vehicles. However the Rumbler, while no louder than a conventional siren, physically disturbs the interior space of cars in its path. With the move from treble to bass, drivers’ bodies vibrate, and their rear windows tremble.

Tom Morgan, vice president for sales and marketing for the company that makes the Rumbler, is quoted in the Washington Post:

Morgan said the Rumbler was developed after police departments complained that, increasingly, motorists weren’t responding to traditional lights and sirens.

“The basic idea is we become more insulated in our vehicles with stereos, iPods and telephones,” Morgan said. “We thought it would be helpful if there was something else along with the traditional siren that would reach a different level of awareness.”

Sonic technologies, again and again, are implicated in arms races. During arms races, as we learned during the Cold War, defensive maneuvers (like shields and headphones) only seem passive – in fact, they provide the impetus for more aggressive modes of penetration, extending a vicious cycle. Our reliance on simple technological solutions to complex problems like noise invites exactly this kind of frustration.

Thanks to Connor for the original link.