Car alarm the main reason why loud bass frequency sound (loud music, other cars or motorcycles with loud exhaust systems, thunderstorms, etc.) can set off car alarms. The second possible reason is that some parts of the alarm system may be improperly installed. Car alarm A car alarm is an electronic device installed in a vehicle in an attempt to discourage theft of the vehicle itself, its contents, or both. Car alarms work by emitting high-volume sound (often a vehicle-mounted siren, klaxon, pre-recorded verbal warning, the vehicle's own horn, or a combination of these) when the conditions necessary for triggering it are
Horn (acoustic) the instrument more difficult to play. Acoustic horns are found in nature in the form of the burrows constructed by male mole crickets to amplify their song. "Gryllotalpa vineae" digs a carefully smoothed burrow with no irregularities larger than 1 millimetre. Its song is loud enough to make the ground vibrate; its 3.5 milliwatts of mechanical power delivers a peak of 92 decibels at a distance of one metre. The song can be heard up to 600 metres away. Horn (acoustic) An acoustic horn or waveguide is a tapered sound guide designed to provide an acoustic impedance match between a