The Cine Technician (1939)

Juno-July, i<)37 THE C 1 N E-T EC UN If I AN 67 The new dynamic unit, termed the 594-A receiver, is capable of handling a greater volume of sound than any previous units employed. It also has a superior frequent v characteristic, especially in the high-frequency register. The principal limitations of present theatre loud-speaker arrangements is poor directional characteristics. The conventional type of tapered horn projects sound through a relatively large area at the lower frequencies, but as the frequency range is increased the distribution suffers, and at high frequencies the sound becomes concentrated into a narrow beam. The result is that it is not possible to obtain a satisfactory balance between the high and low frequencies at the sides of an auditorium, through the falling-off of the high frequencies, and the reproduction becomes "boomy." The cullular horn used in the Diphonic loud-speaker combination successfully overcomes this trouble. The sound from the dynamic unit travels down the common "throat" of the speaker and then divides into the separate channels formed by the individual horns which form the cellular horn. The result of the dividing up of the sound amongst a number of small horns in this manner is that the sound does not become concentrated into a narrow beam along the axis of the main horn at high frequencies, but is evenly distributed in a wide beam which covers the auditorium evenly. Both the dynamic units on the cellular horn and the low frequency speaker have energised fields. These fields, each of which are rated at 24 volts, 1 amp., are supplied with power from a rectifier power unit employing Tungar bulbs. The speech input to the speaker system i> distributed to the high ami low frequency speakers 1>\ means of a dividing network, which introduces attenuation of approximately 12 db. per octave above and below the cross-ovei frequency of 300 cycles. The network is built into a unit which is separate from the main amplifier. This unit also includes a receive] testing panel which enables the operator to test the units on the cellular horn and low frequency unit. The design of the Di-phonic loud-speaker system is such that it takes up very little space backstage and can be arranged in such a manner that it can either be flown or mounted on a framework on castors, so that it can be moved off stage to enable the stage to be used for other presentations. Don't Sign in a Hurry ! The attention of the General Council has been drawn to one or two members who have signed long-term contra* ts for a junior job which also bind them to doing a higher grade job, if required, at the same junior salary. The Council wishes to emphasise the undesirability of this, and to remind members that not merely their own interest but their responsibility to the other members of the Association demands a refusal on their part of such terms if offered. The General Council asks all members to acquaint themselves with the Association's minimums for their particular grades. If you are in any doubt about the terms of your contract don't sign in a hurry but consult the Secretary or the Organiser. SOUND RECORDING WITH Guaranteed First-Class Results Ever/ facility available : RE-RECORDING FROM TRACKS RE-RECORDING FROM DISCS ORCHESTRA RECORDINGS COMMENTARY RECORDINGS With Free Use of Sound Effects Library. 100% EFFICIENCY AND SERVICE AT BRITISH SCREEN SERVICE 54-58 WARDOUR STREET, W.I Gerrard 6543-4 the filmcraft each 3/6 net filmcraft illustrated by Adrian Brunei series from all booksellers An epitome of the technique of film production. Every step, from the choice of subject to the final editing, clearly explained by an expert. With appendices by other well-known technic ians, film technique by v. i. Pudovkin Pudovkin ranks with the greatest Directors of the cinema and the influence of this pioneer work is found in every modern film. making home movies by d. charies ottiey \n up-to-date handbook showing how successful pictures are made and containing many useful hints on technical points which enable the keen amateur to acquire proficiency in tin art of movie-making home processing by Percy W. Harris Even though you prefer to get your processing done lor von, this book will well repay perusal, for with closer knowledge of what the film "j>oes through" will come greater skill and care in the "taking" of your pictures. film titling by G. P. Kendall Types of lettering, the use of home-made and commeri titling outfits, lighting, expo, ure, animated and trick titles all comprehensively explained. film acting by V. I. Pudovkin "This book .... with its reconsiderations and clarifications of film problems is invaluable to anyone who recognises a future (and a past) lor the Cinema as a serious art." The Listener. Eai h 3 6 net or 3 9 post free from : GEORGE NEWNES LIMITED Tower House, Southampton St., Strand, London, VV.C.2