Movietone Bulletin (September 1928)

VOLUME I, No. 35 SEPT. 1, 1928 Capacity and Overload ROM several movietone projecF tionists has come complaint of theatre managers demanding increase in sound until the set was overloaded and distortion, oscillation and other troubles set up. This same thing was just recently laid before me by no less person than Harry Rubin, Supervisor of Projection for the great Publix Theatre chain, whereupon it was decided to devote space to it. In the first place, the conditions of each installation are very carefully observed by competent engineers from the Western Electric and Fox Case organizations and a set is installed which has ample capacity for the theatre. It must however be clearly understood that by “ample capacity” it is meant that the set has ample capacity to provide all the sound that is necessary to secure the best possible effect if the panel setting be what the instructions cail for. It is not meant, however, that the set will provide any great amount of sound over and above what will give the best effect, and right there lies the base of most trouble. Some theatre managers, we are sorry to say, do not use the best of judgment in the matter of sound volume. They apparently argue that if some sound is good, an uproar is, perforce, better, hence they demand what amounts to an uproar of sound, and that of course may result in overloading the set. A medium volume of sound is far preferable to too much. What may well be termed overloading the auditorium with sound is to be very carefully avoided. As we have many times told you, the fader should be carefully cued for each scene in each production. The sound volume should not, and for best general results must not exceed that which will enable those in the rear seats who have normal hearing to listen without discomfort. In making this distance test it is important that the one or those seated in the rear seats have hearing of normal acuteness. Those of dull hearing, it may reasonably be expected, will seat themselves nearer the screen. It should never be that there is actual need for overloading a set, unless it be that changes are made in the auditorium itself which alter the sound volume necessity. Actual overloading should be made evident by unsteadiness of the amplifier plate current meters. However it must be understood that an effect very similar to overloading, such as distortion of sound and oscillation, may be caused by a reverberant house—an auditorium which has too much hard surface exposed. This effect is made worse by increased volume. An auditorium of this sort may be “cured” by covering a portion or all of its walls with cloth, such as may be had for the purpose in very lovely patterns. The cloth may be set in moulding panels, and may lay flat upon the wall surface. Of course it is quite true that the size of the set must be such as will fit the auditorium, but since local conditions in the auditorium itself have a great deal to do with (Continued on last page, Col. 3) Fader at Zero It not infrequently happens that there will be a considerable space between voice or other sound it is desirable to reproduce. This is especially true in the news reel. In cueing the fader these sections should be marked zero, and the fader should be set at zero during their duration, since otherwise there may be more or less pronounced surface noise audible to the audience. Another thing, in making the change-over, some movietone projectionists do not handle the fader as carefully as they should. The fader must be shifted, if possible, with one even-speed movement. If you find you cannot do this, then move it at even speed to zero, stop, move your hand and then repeat the process, but don’t go too far and find yourself obliged to reduce the sound. Your cue sheet should show the correct setting. Reach that setting exactly and stop, except as before remarked, if the cueing was done with an empty auditorium, you may have to boost the reading a point or two. Use Heavy Oil Oil spattered film is terrible. It is utterly inexcusable. The effect is worse than bad. If your intermittent oil well bearings show inclination to seep oil out, use heavy oil. In fact, I’m inclined to believe that in such cases it won’t be a bad stunt to try high grade vaseline. However, before doing that set the oil seepage matter before the projector manufacturer and ask his sanction to the use of vaseline, or such equivalent as he may recommend.