A loudspeaker is a device that converts electrical signals into audible sound waves. Before electricity, amplification was obtained by using an acoustical horn of the type seen on gramophones. The invention of the speaker came with the development of...

A loudspeaker, speaker, or speaker system is an electromechanical transducer that converts an electrical signal into sound. The term loudspeaker can refer to individual devices (or drivers), or to complete systems consisting of an enclosure...

Australia's largest city has installed dozens of loudspeakers to tell residents what to do in a terrorist attack, an official said Wednesday.Around 40 speakers should be operational in time for next month's meeting of 21 world leaders at the Asia Pacific Economic Cooperation summit, New...

A British Muslim who led an angry crowd in chants of "Bomb, bomb, Denmark, bomb, bomb USA" during protests of cartoons of the Prophet Muhammad was found guilty Friday of incitement to murder.Umran Javed, 27, was one of the leaders of a Feb. 3 rally...