When.com Web Search

Search results

1. Results From The WOW.Com Content Network

2. Air horn - Wikipedia

   en.wikipedia.org/wiki/Air_horn

   An air horn is a pneumatic device designed to create an extremely loud noise for signaling purposes. It usually consists of a source which produces compressed air, which passes into a horn through a reed or diaphragm. The stream of air causes the reed or diaphragm to vibrate, creating sound waves, then the horn amplifies the sound making it louder.

3. Vehicle horn - Wikipedia

   en.wikipedia.org/wiki/Vehicle_horn

   A horn grille is a part of some designs of car or other motor vehicle that has an electric horn, such as a motor scooter. Larger, louder air horns, as found on trucks (lorries) and buses, are driven by air compressors, or supplied by reservoirs charged to operate their air brakes. The compressor forces air past a diaphragm in the horn's throat ...

4. Long-range acoustic device - Wikipedia

   en.wikipedia.org/wiki/Long-range_acoustic_device

   An NYPD LRAD on top of a police humvee An LRAD operator wearing hearing protection LRAD on a navy ship. A long-range acoustic device (LRAD), acoustic hailing device (AHD) or sound cannon is a specialized loudspeaker that produces sound at high power for communicating at a distance.

5. Horn (acoustic) - Wikipedia

   en.wikipedia.org/wiki/Horn_(acoustic)

   A patent horn loudspeaker. Loudspeakers are often built into horn-shaped enclosures or use horns. Most often the higher-frequency elements (tweeters and midranges) use horns, sometimes with acoustic diffraction lenses to spread the sound waves in a horizontal pattern at ear-level and limit the vertical pattern. An audio driver (e.g., a speaker ...

6. Emergency vehicle equipment - Wikipedia

   en.wikipedia.org/wiki/Emergency_vehicle_equipment

   A fire truck uses an air horn to alert cars of its presence. Air horn - These devices force compressed air from the vehicle's air brake system against a diaphragm, creating a loud noise. Air horns used on emergency vehicles usually have a distinctive tone so they can easily be distinguished from other large vehicles, commanding urgency.

7. Train horn - Wikipedia

   en.wikipedia.org/wiki/Train_horn

   A train horn is an air horn used as an audible warning device on diesel and electric-powered trains. Its primary purpose is to alert persons and animals to an oncoming train, especially when approaching a level crossing. They are often extremely loud, allowing them to be heard from great distances.