A lacquer disc is
|“||a type of phonograph record created by using a recording lathe to cut an audio-signal-modulated groove into the surface of a special lacquer-coated blank disc.||”|
The lacquer disc "format replaced wax matrices used for recording and mastering in the mid-1930s and was the dominant format for making original, or master, recordings until they were supplanted by magnetic tape in the late 1940s. Lacquer discs are often referred to as acetate discs, or acetates, even though the term misstates the composition of the discs. Lacquer instantaneous discs are composed of a nitrocellulose lacquer layer applied to an aluminum, glass, or steel base. Discs made during World War II often have a glass base because of wartime rationing of aluminum, and these are extremely fragile. The thin lacquer layer on new discs was blank, without grooves. The material was soft enough to be inscribed with grooves by a cutting stylus and resilient enough to survive several playbacks. Lacquer discs were used to record radio programs, field recordings, and other "live" events. Many companies offered transcription services in the 1930s that produced instantaneous discs on demand. Those made by radio networks and others for professional purposes were usually 16 inches in diameter. Discs recorded for personal purposes were likely to be of a smaller diameter, from 7 inches to 12 inches.