The Rumbler was developed by Federal Signal Corporation as an "intersection clearing device". The Rumbler is about 10 decibels quieter than a standard emergency vehicle siren and is generally activated in eight-second bursts by depressing the horn button in a Rumbler-equipped vehicle. In addition, the siren's low-frequency thumping sound also causes noticeable vibrations to drivers and pedestrians who are near it and helps to generate attention in high-noise environments like "dense, urban traffic". The lower frequency sound penetrates hard surfaces like glass and doors more effectively than high-frequency tones. The Rumbler produces a pulsating, low-frequency sound between 182 and 400 hertz, and is operated in tandem with a standard, piercing high-frequency siren. Developed in 2007 by Federal Signal Corporation, and sounding at a low-frequency level, it is designed to be heard by motorists who may otherwise be unable to hear high-frequency sirens due to ambient noise, such as urban traffic. A Rumbler siren is a type of emergency vehicle siren used primarily in the United States.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |