A sound wave moving through the atmosphere pushes air. As the air in front of the wave gets compressed, the air pressure goes up. The magnitude of change in the air pressure from that sound wave is its amplitude. The bigger its amplitude, the louder the wave will sound.
Acetate stock was used as a base for motion picture film, sound film, and magnetic tape predominantly between the 1950s and the 1980s. Acetate stock replaced the flammable nitrate stock that had been the base for 35mm theatrical film during the first half century of the motion picture era. It is
A sync-pop is a 1kHz tone that is exactly one film frame in duration, used for matching picture and sound negatives together. The sync-pop must occur exactly two seconds (or three feet) before the first frame of picture (FFOP) in a film reel. If the picture negative contains a standard Academy