Movie Makers (Jan-Dec 1948)

MOVIE MAKERS 209 tion will give cleaner reproduction at normal volume. For detecting slow variations of film speed, commonly known as "wows," recordings of the piano are most suitable. A violin or cello record is perhaps as good a test as any for freedom from more rapid speed variations, which manifest themselves as a sort of roughness or gurgling quality of tone rather than perceptible changes of pitch. FREQUENCY RANGE Two intimately connected points of performance are the tonal or frequency range of the projector sound system and the amount of background noise it produces. (Background noise refers to the noise that issues from the loudspeaker, not to the noise produced by the running of the projector mechanism.) A good 16mm. sound projector is capable of reproducing with nearly uniform intensity all sound frequencies from 100 vibrations, or cycles, a second to at least 5000 a second. A projector which has adequate high frequency response will reproduce in a natural manner the high-pitched, hissing sound of the letter S in speech. When high frequency response is inadequate, the sound of the S in "sat" is much more like that of the TH in "that." If there is good high frequency response there should be adequate low frequency response in order to balance the tonal quality. Orchestral music is best for judging balance. TONAL BALANCE The observer should be aware, in this connection, that apparent tonal balance between high and low frequencies is likely to be very largely a matter of personal taste; a matter which in quite a few instances is conditioned by the type of radio receiver to which the listener has become accustomed. It is highly desirable, therefore, that comparisons of tonal balance should be judged by a number of observers. It is perhaps wiser to concentrate attention on the factor of intelligibility, rather than to depend too much on judgment of tone balance. When tone quality is changed by means of the usual tone control, it will be noticed that the background noise changes greatly, with relative emphasis placed on the higher or lower frequencies. The projector which reproduces a wide frequency range will always produce more background noise than a projector having a narrow frequency range. Reproduction of high frequencies is almost unavoidably accompanied by reproduction of hissing sounds from the film, from the photocell and from other parts of the amplifying system. Reproduction of low frequencies A Moneysaver for Home Movie Makers mswoLP "JUNIOR" SPLICER This smaller model of the famous GRISWOLD film splicer was developed specially for home movie makers. It makes splicing so easy that any home movie maker can do a professional job and save the cost of sending films out to be spliced. These savings will quickly pay the cost of the GRISWOLD Junior — a cost that is surprisingly low. Ask your photo dealer for descriptive Bulletin 10. Ij he can't supply you, write to our distributor. NEUMADE PRODUCTS 427 WEST 42nd STREET, NEW YORK, N. Y. GRISWOLD MACHINElWORKS DEPT. A, 410 MAIN STREET, PORT JEFFERSON, N. Y. YOU'LL LIKE fca, f%*C&tC WITH YOUR %W^ Jv *TrFB *$ Let recorded music emphasize the mood of your film — give it smoother continuity. IT'S EASY AND ECONOMICAL WITH A FIDELITONE Dual Turntable • Just drop us a card to receive your FREE copy of "Melodious Accompaniment" and illustrated literature about FIDELITONES Fidelitone GEORGE K.CULBERTSON CO. 5133 JUANITA AVENUE • DEPT. M MINNEAPOLIS 10, MINNESOTA