The speaker was invented in 1876
Have you ever wondered who invented the loudspeaker? We use it every day, maybe not literally, but at least we hear. We got loudspeakers at the phones, radio, TV, in the car, at work, and why not to each party. The loudspeaker has become indispensable in our lives, but it also has an interesting history.
Alexander Graham Bell invented the first loudspeaker in 1876. Bell invented the loudspeaker because he needed a device that would amplify sound for the telephone. In 1877, Ernst Siemens from Germany invented an improved type of loudspeaker.
The modern design of moving-coil (also called dynamic) drivers was established by Oliver Lodge in 1898.The first practical application of moving-coil loudspeakers was established by Danish engineer Peter L. Jensen and Edwin Pridham, in Napa, California. Jensen was denied patents. Being unsuccessful in selling their product to telephone companies, in 1915 they changed strategy to public address, and named their product Magnavox. Jensen was, for years after the invention of the loudspeaker, a part owner of The Magnavox Company. The moving-coil principle commonly used today in direct radiators was patented in 1924 by Chester W. Rice and Edward W. Kellogg. The key difference between previous attempts and the patent by Rice and Kellogg is the adjustment of mechanical parameters so that the fundamental resonance of the moving system is below the frequency where the cone’s radiation impedance becomes uniform.
A loudspeaker (or loud-speaker or speaker) is an electroacoustic transducer; a device which converts an electrical audio signal into a corresponding sound. Speakers are typically housed in an enclosure which is often a rectangular or square box made of wood or sometimes plastic. Where high fidelity reproduction of sound is required, multiple loudspeakers may be mounted in the same enclosure, each reproducing a part of the audible frequency range (picture at right). In this case the individual speakers are referred to as “drivers” and the entire unit is called a loudspeaker. Miniature loudspeakers are found in devices such as radio and TV receivers, and many forms of music players. Larger loudspeaker systems are used for music, sound reinforcement in theatres and concerts, and in public address systems.