78 (r.p.m. disc)
Extract
(r.p.m. disc)
Generally a shellac disc of 10- or 12-inch diameter, recorded and played back at 78 r.p.m., and having a playing time of three to four minutes per side; see Recording §I 1., (i). The last commercially issued 78 r.p.m. discs from the mid-1950s onwards were often pressed on vinyl rather than shellac....
