New Police Siren Rumbles Drivers to Attention

While jamming out to AC/DC or 50 Cent with the volume cranked, a driver may cruise for miles before taking a glimpse in the rear view mirror and seeing a police car with its sirens blaring. Fed up with the increase in driver delays, police departments are hoping to shake drivers to more immediate attention with a new invention called the Rumbler™.

Referred to as an "intersection clearing system", the Rumbler produces low-frequency tones that duplicate the sounds of a siren. But rather than just make a loud noise, these tones actually shake solid material – making drivers feel the sound waves from a police car’s siren. The effects of the Rumbler can be felt up to 200 feet ahead of a police car, and inattentive drivers suddenly may notice their vehicles quaking or see their rear view mirrors quivering. Even if a driver can’t hear a siren due to loud music, hearing impairment or general distraction, he or she will be quickly alerted to its presence. The Rumbler also gives drivers and pedestrians a better sense of where a siren is coming from, which they don’t always get from their ears.

The company behind the Rumbler is Federal Signal, a leading supplier of audible and visual warning devices for police, fire, ambulance and other emergency vehicles. Compatible with most 100/200-watt emergency siren amplifiers, a complete Rumbler system consists of an amplifier, a timer, two sub woofers and vehicle-specific mounting hardware. When connected to a police car, the Rumbler senses the tone signal of the car’s siren, produces a tone that is 75-percent lower in frequency and amplifies that tone through the pair of high-output woofers.

Federal Signal is quick to note that the system is meant to be an effective emergency backup and not simply used for routine traffic stops (unless necessary, of course). The device is ideal for use in urban areas that are crowded with traffic and/or pedestrian activity – like busy intersections (which is why they call it an "intersection clearing system"). It is also not meant to be used for long periods of time. The Rumbler automatically shuts off after 10 seconds, which Federal Signal claims should be more than enough time for a police car to clear out a congested area.

Currently, the Rumbler is being adopted by agencies on the East coast, particularly in larger cities with dense urban areas. Washington, D.C., now has 49 cars equipped with Rumblers, and expects all of their cars to incorporate the technology in the next four years. But smaller areas like Lower Allen Township in Pennsylvania (just outside of Harrisburg) are also trying out the new technology. With reasonable costs (around $350 to equip each police car), it’s possible drivers could feel the rumble of a lot more sirens in the near future.

Federal Signal's The Rumbler
Technical Specs and Product Literature