International photographer (Jan-Dec 1934)

Ten The INTERNATIONAL PHOTOGRAPHER January, 1934 Motion Picture Sound Recording Chapter V HE preceding chapter described the sound stage jfe||| and the equipment used on it, and mentioned briefly the types of portable recording equipment employed for location work. This chapter begins the discussion of the permanent monitoring equipment that is associated with each sound stage. The monitor man, who is also called the "mixer," or first soundman, has perhaps the most responsible position in connection with the recording of sound ; for it is he who governs the volume and, to some extent, the quality of the sound that is recorded. The volume of sound, or rather its electrical equivalent, he regulates by means of his monitoring controls; and by locating the microphones so that they take advantage of the favorable acoustic conditions existing within a set, he is able to influence in a considerable degree the quality of the recorded sound. Monitoring at its best is an art ; at its worst the result is a confused jumble of sound that is decidedly unpleasant to hear. Monitoring requires a high sort of skill on the part of the monitor man, a skill that is developed most readily by intimate acquaintance with the monitoring equipment and with the acoustic conditions normally encountered in motion picture sets. In addition to that special skill, a monitor man must be resourceful and alert, and have a sincere desire to do good work regardless of the labor involved. A theoretical knowledge of the fundamentals of acoustics and sound (the elementary discussion contained in Chapter III should prove sufficient) and broad practical experience in the monitoring of sound motion pictures are necessary requisites in the schooling of a successful monitor man. One other essential that the monitor man must have is tact ; for only if he is possessed of that virtue can he secure the whole-hearted cooperation of the director and the technical staff of the picture on which he is working. o* Switch /vvicrophone Outtput By Charles Felstead Associate Editor person of normal hearing. A knowledge of music and of musical instruments is not indispensable, although it is highly desirable ; but an ear for music is a necessity for the monitor man who does orchestrations. As in any skilled labor, natural abilities make it easier for some men to become more expert monitor men than others. The Permanent Monitoring Installation The permanent monitor room that is associated with each sound stage is usually located adjoining the middle of one of the side walls of the stage. This monitor room is about twelve feet square ; and its floor is about fifteen feet above the floor of the stage. The monitor man looks out onto the sound stage through three glass windows set in a sort of bay, like the bay window of a house. The windows are each constructed of two sheets of thick plate glass solidly mounted about four inches apart. The air space between the sheets of glass provides additional insulation against the passage of sounds originating on the stage. The control desk for the monitor man is placed in the bay formed by the three windows in such a position that he has a clear view of the action taking place in both directions along the stage as well as directly in front of him. One side of the monitor room is open to a large room about thirty by fifty feet in size, the floor of which is on a level with the floor of the sound stage. This large room is known as the monitor theatre, or auditorium ; and S*Vfe "'^fP Controls ih ih ?L -^ lh i^hrf1 ihQ yVyONITOR ROOM Three position y^*m Volume Control To npli room ., , >Amplifier VolumeindKAtof \ r£,nvy, Oextensic meter sion — *■ To boo&terAmplifier k^ Loud Spe&Ker public address amplifier Carbon microphone Fig. 2. Block schematic diagram of stage and monitor room. Normal hearing is, of course, a possession of the most vital importance to the monitor man. If he is not gifted with normal hearing, he is likely to place his microphones so that lie records more high-frequency, or perhaps more low-frequency, sounds than are pleasant to the ears of the the two monitor horns are suspended in the far corner of it facing toward the monitor man's desk. The walls and ceiling of the monitor room and monitor theatre are treated with acoustic materials, that absorb sound, and the floor is covered by a rug laid over a thick padding of hair Please mention The International Photographer when corresponding with advertisers.