Sound Recording And Reproduction

Sound Recording And Reproduction Erpi Classroom Films 13:15:47 Man at rewind table winding 35mm film, stops & looks at picture. CU showing positive picture frames & variable density soundtrack. 13:16:26 Picture Negative & Sound Negative side by side over light table. Print from the two shown by animation. 13:16:40 Narrator, James A. Brill, sitting at desk w/ large microphone. Side view w/ animation showing voice sound waves going to microphone. Wires from microphone w/ converted signals animated thru wire. 13:17:04 Illustration of microphone, amplifier & film recorder shown w/ animation. CU of recorder & lens placing line onto track negative for unilateral variable area track. Bilateral variable area track shown. 13:18:11 Variable density track shown. Three tracks of same sounds shown side by side. 13:18:35 Animation of variable area & variable density shown projected thru slit to photoelectric cell which reads the amount of light & sends the signal to amplifier & then to loudspeaker which converts back to soundwaves. Repeated for review. 13:20:48 Illustration of light valve showing metallic ribbons forming light slot due to acting in magnetic field. 13:21:46 MCU Simple microscope, man adjusting. Diagram of separation of ribbons & hair which is wider. 13:22:01 Light, lens & thru lens system to focus light onto film. 13:22:59 Schematic representation of ribbon; shown moving w/ amplitude of current & changing exposure of film. Brill reading script in MS. 18:24:18 Variable density track moving past w/ violin & orchestra. Variable area track of music. Science; Physics; Motion Pictures; Educational Films; Projection; Communication; Perception; Analog; NOTE: Very good quality.