SOUND FILMS

Evening Post, Volume CXVI, Issue 24, 28 July 1933, Page 12

SOUND FILMS

WESTERN ELECTRIC PROGRESS,

' The improvement in sound films of greatest importance involves what is known commercially as wide or extended

range of reproduction. For its full effect to be apparent corresponding changes must be made in the recording studios, and in the more important studios these' changes have been made. But even without any alteration in recording practice, with an ordinary film in the projector, the installation of wide range (or extended range) in a theatre improves the sound quality to a degree quite striking to the average ear. When both recording and reproduction are of this newer' type the 'difference is comparable to that between' a modern radio and the tinny, horn loudspeakci' model of 1923. .

Sound is caused by the trembling of the string of a violin, of a human vocal cord, or of some other source' of Round; it is the corresponding trembling imparted tp the air around such a source, and lastlyl, by means of the ,air. to the drum of thelistener's ear. The .G-string. of the .violin trembles slowly; . the E-strin'g' rapidly. The number of vibrations per second imparted to the air is greater'^ in the case of the E-striug; the frequency is higher. The greater the frequency of vibration per second, the higher the pitch will be. The musician creates higher frequencies still by placing his fingers upon the string, so that only a shorter portion of it is free to vibrate under the bow. Sound systems ..have commonly been capable of reproducing -with reasonable fidelity every note of every instrument, and every tone of the human voice, for the past several years. But many of the overtones which are necessary to" naturalness have been lost.

Wide or extended range, by reproducing frequencies as low as 20, and above 0000 per second, adds richness and brilliance to music, and individuality and naturalness to the human voice. This is an advance in. technics that even an audience uncritical and uninterested in the mechanics of the entertainment will unmistakably notice and comment upon. Wide or extended range is built to be added to existing , Western Electric installations.