Johann Philipp Reis installed an electric loudspeaker in his telephone in 1861, and it was capable of reproducing clear tones, but later revisions could also reproduce muffled speech.
The first experimental, more modern, moving-coil (dynamic) loudspeaker was invented by Oliver Lodge in 1898. The first practical moving-coil speakers were manufactured by Danish engineer Peter L. Jensen and Edwin Pridham in 1915, in Napa, California. Like previous speakers these used horns to amplify the sound produced by a small diaphragm. Jensen was denied patents. Being unsuccessful in selling their product to telephone companies, in 1915 they changed their target market to radios and public address systems, and named their product Magnavox. [SOURCE: Wikipedia]