International projectionist (Jan-Dec 1936)

July 1936 INTERNATIONAL PROJECTIONIST 25 ; plifier; no amplifier is required at the machine. The same company has also introduced horns of the "multi-cellular" type (Fletcher horn.) The horns are divided into diverging rectangular sections which distribute the sound uniformly over prescribed vertical and horizontal angles, assuring faithful balance at all frequencies. A new receiver having an efficiency about 100 per cent higher than any unit heretofore produced has also been developed. One to four receivers may be attached to a horn. Special throats are employed for connecting the receivers to the horn; the spaces surrounding the diaphragms of the receivers are specially designed to couple the diaphragms with the air columns of the horn efficiently and without distortion. The total depth of the horn is about 40 inches, thus allowing practical and convenient backstage arrangement. RCA announced new high-fidelity, a. c. operated reproducers employing the rotary stabilizer form of control, and having increased power output and optional speaker complements to suit the requirements of individual theatres. Progress in Projection Field Projectors and Accessories. — The past year has seen a definite trend toward high-intensity projection by theatres of small and intermediate size, replacing the low-intensity reflector arc which has been in almost universal use in theatres of these classes. This change in projection practice has been made possible by the development of the Suprex projector carbons, together with improved lamps for their operation. Now that these new carbons and lamps have placed high-intensity projection within economic reach, the smaller theatres are rapidly availing themselves of the advantages already demonstrated in that respect by the large down-town theatres, in which highintensity projection lamps have been in use for a number of years. The theatre-going public has definitely shown its preference for the improved quality of projection light, the superior projection of color features, and the higher level of general illumination that high-intensity projection makes possible. For some time there has been a demand by a number of the larger theatres for still more intense illumination than could be supplied by the 13.6-mm., highintensity projection carbon operated at 120-130 amperes. This demand has now been met by the development of a 13.6mm., super-high-intensity carbon adapted to steady operation over a current range of 140-190 amperes. At the upper limit of current this new super-high-intensity carbon provides 30 per cent more light than the regular 13.6-mm., high-intensity carbon. There is also a more uniform distribution of brilliancy across the face of the crater of the new carbon, resulting in less contrast in screen illumination between the center and the sides or corners of the screen. The lamp companies have recently made available an 8-volt, 2-ampere T-8 bulb sound-picture reproducer lamp of improved characteristics. This lamp, in Like honey to a bee Movie fans know quality projection when they see it. They may not recognize the qualities of a Super Cinephor by the technical names of Definition, Contrast, Brilliance, etc., but they appreciate the composite result of finest quality pictures. That is why a Super Cinephor attracts customers. Remember, one more customer a day pays for a Super Cinephor in only one year. For complete details write to Bausch & Lomb Optical Co., 616 St. Paul Street, Rochester, N. Y. BAUSCH & LOMB SUPER-CINEPHOR THE FOREST TWIN 50 COPPER-OXIDE RECTIFIER For 2 Projection Arcs-- AND A SPOT! • LIST PRICE: $500 • • FOREST Twin 50 is the ideal power supply for TWO Suprex arcs, of 30 to 50 amperes each. It will also supply a 30 to 60 ampere regular carbon arc Spot Lamp, 50 to 55 volts. • SEE your dealer today, or write to us for detailed information about this up-to-the-minute rectifier development for modern projection arcs. Circular Upon Request FOREST MFG. CORP. Rectifier Specialists Belleville New Jersey U. S. A. FOREST TYPE TWIN 50 C-O RECTIFIER —employs the copper oxide units, insuring long life and quiet, trouble-free and efficient operation— all with a maintenance cost that is nil.