Specifies basic technical characteristics for magnetic sound test films used for checking, adjusting and measuring 70 mm motion-picture projector sound systems and sound reproduction channels of motion-picture installations. Includes specifications for test films intended for checking, adjusting and measuring of azimuth of the magnetic head gaps; output level balance of several motion-picture projectors or systems and interchannel balance on each projector or system; frequency response of the sound reproduction channels and non-uniformity in velocity of film travel.