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Siren at the Walter P. Chrysler Museum in 2011. The Chrysler Air Raid Siren is an outdoor warning siren produced during the Cold War era that has an output of 138 dB(C) at 100 feet.
Upsweep is an unidentified sound detected on the American NOAA's equatorial autonomous hydrophone arrays. This sound was present when the Pacific Marine Environmental Laboratory began recording its sound surveillance system, SOSUS, in August 1991. It consists of a long train of narrow-band upsweeping sounds of several seconds in duration each.
There are 8,200 alarm sirens for civil protection throughout Switzerland. They are tested once a year, on the first Wednesday in February. [1] Sound sample ⓘ An 1860s-era siren. [2] A siren is a loud noise-making device. There are two general types: mechanical and electronic.
Sound sample ⓘ A civil defense siren is a siren used to provide an emergency population warning to the general population of approaching danger. Initially designed to warn city dwellers of air raids (air-raid sirens) during World War II, they were later used to warn of nuclear attack and natural disasters, such as tornadoes (tornado sirens).
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. It has been used as a method of crowd control , which has caused permanent hearing damage , having an extremely high decibel capacity (up to 160 dB measured at one ...
Acoustic mirrors at RAF Denge. Before World War II and the invention of radar, acoustic mirrors were built as early warning devices around the coasts of Great Britain, with the aim of detecting incoming enemy aircraft by the sound of their engines.
The effect was first reported by persons working in the vicinity of radar transponders during World War II. In 1961, the American neuroscientist Allan H. Frey studied this phenomenon and was the first to publish information on the nature of the microwave auditory effect.
Before the film's release, the popular band Spike Jones and His City Slickers, noted for their parodies of popular songs of the time, released a version of Oliver Wallace's theme song, "Der Fuehrer's Face" (also known informally as "The Nazi Song"), itself a parody of the Horst-Wessel-Lied, in September 1942 on RCA Victor Bluebird Records #11586. [11]