The term "Auxetophone" refers to a device or machine invented in the late 19th century that was used to amplify sound. It comes from the combination of two words: "auxeto," meaning growth or increase, and "phone," denoting sound or voice. The Auxetophone was specifically designed to augment the volume of audio recordings or live performances, making it an early form of amplification technology.
Initially developed by Sir Oliver Lodge, a British physicist and inventor, the Auxetophone utilized the principle of magnetostriction, which is the phenomenon of a material changing shape or size when exposed to a magnetic field. The device consisted of a cylindrical tube made of ferromagnetic material, typically iron, wrapped with a coil and placed near the source of sound. As an alternating current passed through the coil, it created a varying magnetic field that induced magnetostriction in the tube. This caused the tube to expand and contract, essentially acting as a mechanical amplifier for sound waves.
The Auxetophone was considered revolutionary at the time, as it allowed for a significant increase in the audibility of audio recordings and live performances without the need for electronic amplification. It found applications in various fields, including telephony, public address systems, and even early attempts at reproducing music. However, its usage gradually waned with the advent of more advanced amplification technologies, such as vacuum tube amplifiers.
Overall, the Auxetophone represents an important milestone in the history of sound amplification, paving the way for subsequent developments in audio engineering and reinforcing the human desire to enhance and expand the power of sound.
