The first working loudspeaker was invented by Alexander Graham Bell who incorporated the device into his other famous invention, the telephone. Bell was awarded the patent for the telephone in 1876 with the loudspeaker device included in the patent. However, the initial concept for the loudspeaker device was first developed in 1874 by a German inventor named Ernst W. Seimens.
Although another inventor named Johann Phillip Reis also had a loudspeaker in his own telephone invention in 1861, the speaker was only able to reproduce tones and unintelligible speech. Seimens patented the principle of the dynamic or moving-coil transducer with a circular wire in a magnetic field, which inspired Bell to invent his own telephone loudspeaker.
Seimens could have easily been recognized as the inventor of the loudspeaker if not for one mistake; he patented his device as a magneto-electric apparatus and he did not use it to transmit or recreate audio. A year after the patent for the loudspeaker was granted to Bell, Seimens applied for a patent for a modified version of Bell's loudspeaker. His application was granted a year later and the diaphragm design of his patented loudspeaker came to be the iconic trumpet-like speakers of the phonograph.
A number of patents for modified loudspeaker devices were applied for by other inventors within the next few years. These inventors included Oliver Lodge, Jonathan Stroh, Anton Pollak, Edwin Pridham and Peter Jensen.