International projectionist (Jan-Dec 1935)

30 INTERNATIONAL PROJECTIONIST May 1935 Your Iheatre needs this TEST REEL • No longer need you be in doubt about your projection equipment delivering highest possible quality results. These reels, each 500 feet long, are designed to be used as a precision instrument in testing the performance of projectors. • The visual section includes special targets for detecting travel-ghost, lens aberration, definition, and film weave. The sound section includes recordings of various kinds of music and voice, in addition to constant frequency, constant amplitude recordings for testing the quality of reproduction, the frequency range, the presence of flutter, and 60-cycle or 96-cycle modulation, and the adjustment of the sound track. • For theatres, review rooms, exchanges, laboratories and wherever quality reproduction is desired. These reels are an S.M.P.E. Standard, prepared under the supervision of the Projection Practice Committee. "Invaluable. The finest technical contribution to the projection field since sound pictures were introduced." — HARRY RUBIN, Director of Projection, Publix Theatres. "No theatre that serves its patrons well should be without these test reels. Simply great."— R. H. McCULLOUGH, Fox West Coast Service Corp. "Eliminates all excuses for poor reproduction. Projectionists know just where they stand through the aid of these reels. I recommend them unqualifiedly." — THAD BARROWS, Publix Theatres, Boston, Mass. Price: $37.50 Each Section Including Instructions Address: SOCIETY OF MOTION PICTURE ENGINEERS Hotel Pennsylvania New York, N. Y STUDIO AND THEATRE SOUND PICTURE ADVANCES CITED (Continued from page 10) conditions are not desirable for musical reproduction. The most desirable arrangement, he suggested, might be to use two sound tracks and two complete reproducing systems so that dialogue could be reproduced over a system similar to that now employed, and the music through a system utilizing an entirely different loudspeaker arrangement, preferably one that would diffuse the sound and spread the sources over a greater area so as to increase its reverberance. For the present, however, Mr. Batsel said, the best results can be obtained by providing more satisfactory reverberation and good tonal characteristics on the recording stages in the studios. To this end, studio technicians were urged to adopt the known standards for producing more pleasing "tone design" which have been established with audiences over a great period of time in church buildings, concert halls and opera houses. With the development of a skillful technique for adding sound effects, eliminating undesirable sounds from the original "takes," and other dubbing almost no feature picture is released today without more or less re-recording. New RCA Sound Track Several of the RCA engineers, in their papers, referred to the development of a radically new system of noiseless sound recording called "push-pull" or "double sound track" as an ideal one for making the original sound track.1 The new "push-pull" system, they said, makes possible the complete elimination of ground and hissing noises, gives a greater range of volume shadings and overall fidelity of reproduction over the entire audible range of sound. In operation, the sound waves are halved into two separate but symmetrical sound tracks, one negative and the other positive, automatically eliminating the blank unused portion of the sound track which was previously responsible for the background noise. This means that in original "takes" the recordist does not have to take time out to make critical adjustments of a delicate noise reduction system. Also, in the re-recording process, the producer is enabled to vary the character of the sound in the final prints to suit the requirements of individual theatres. Recent Important Improvements Mr. Batsel enumerated some of the important recent developments toward the elimination of distortion which bring sound pictures nearer the ideal of real ism and tone fidelity. These develop ments were covered in detail by RCA engineers in separate papers, but he summarized them as follows: 1. Development of film-moving mech anisms free from objectionable variations of speed, notably the magneticallydriven drum in the recorder, and the "rotary stabilizer" in the reproducer. Elimination of flutter caused by film gate construction and ripples produced by the sprocket holes. 2. Improvement of recorder optical system so that it is capable of satisfactorily recording a frequency range from 40 up to 10,000 cycles. 3. Improvement of amplifiers through development of new types of vacuum tubes, improved transformers and resistors. 4. New laboratory devices for analysis of causes of distortion so that they might be eliminated. 5. New types of microphones. These are of the velocity type, having a smoother response over a wider frequency range than previous types, and fulfill the requirement for a directional microphone having characteristics independent of frequency. In the development of these microphones there has also been considered some of the more fundamental factors essential for further improvement in sound recording. e I 'Described in detail elsewhere in this issue. — Ed. L.U. 306 Retains I. A. Control Local 306 voted overwhelmingly to retain I. A. control over its destinies, at a recent meeting presided over by President George E. Browne and Vicepresident Harland Holmden, Cleveland, who has been in control of the union since July 7, 1933. Holmden read a report of I. A. stewardship to date, which revealed that the local was broke when the I. A. assumed control but now has $100,000 cash on hand. A hearing on the N. Y. City wage scale promulgated by the NRA was to have been held June 4 in Washington. Details of this scale appear elsewhere in this issue.