Search Results for: Disc harrows
of the disc. at first, the discs were commonly made from shellac ; starting in the s polyvinyl chloride became common. in the mid- s, gradually, records made of any material began to be called vinyl records, or simply vinyl. the phonograph disc record was the primary medium used for music reproduction
, ⁄ rpm; sp [single], -inch disc, rpm, or -inch disc, rpm; ep [extended play], -inch disc or -inch disc, ⁄ or rpm); their reproductive quality, or level of fidelity (high-fidelity, orthophonic, full-range, etc.); and the number of audio channels ( mono , stereo , quad , etc.). records may be scratched...
https://en.wikipedia.org/wiki/Gramophone_record