hi-fi

Phonograph Pho"no*graph, n. [Phono- + -graph.] 1. A character or symbol used to represent a sound, esp. one used in phonography. [1913 Webster]

2. (Physics) An instrument for the mechanical registration and reproduction of audible sounds, as articulate speech, etc. It consists of a rotating cylinder or disk covered with some material easily indented, as tinfoil, wax, paraffin, etc., above which is a thin plate carrying a stylus. As the plate vibrates under the influence of a sound, the stylus makes minute indentations or undulations in the soft material, and these, when the cylinder or disk is again turned, set the plate in vibration, and reproduce the sound. [1913 Webster]

3. an instrument for reproducing sounds, especially music, previously recorded on a plastic cylinder or disk as a pattern of bumps or wiggles in a groove. A needle (stylus) held in the groove is made to vibrate by motion (rotation) of the recording, and the vibrations caused by the bumps and wiggles are transmitted directly to a membrane, or first to an electronic amplifier circuit, thereby reproducing with greater or less fidelity the original sounds. A phonograph which is equipped with electronics enabling the playback of sound with high fidelity to the original is often called a {hi-fi}.

Note: In the 1990's such devices are beginning to be replaced in many homes by compact disk players; the production of plastic recordings of music for playback on a phonograph has almost ceased for entertainment purposes. [PJC]