Modern Theater Loud Speakers and Their Development

Although many of the basic ideas involved in the operation of present-day loud speakers were conceived during the early stages of the development of the telephone, it was not until the advent of the vacuum tube amplifier that these principles were applied to the design of structures capable of delivering sufficient acoustical power to be audible throughout a room or auditorium. Having reached this stage, however, the developments that culminated in the sound reproducing systems employed with present-day sound pictures came in rapid succession. These developments have embraced all phases of loud speaker design, with the result that systems are now available that convert from 25 to 50 per cent of the electrical input into acoustical output, and maintain conversion efficiencies of this order of magnitude over a frequency range of 50 to 10,000 cps. These systems are so designed as to be capable of reproducing the recorded sound at intensities that not only greatly enhance the dramatic effect of the presentation in the theater, but also open entirely new fields in recording. All these improvements have been attained with a reduction in distortion and improved fidelity of the reproduced sound. The directional properties of the loud speakers also have been markedly improved, with the result that the better quality of reproduction achieved is available throughout the entire seating area and the undesirable beam effects previously experienced have been eliminated.

Print ISSN

0097-5834

Published

1937-03

Content type

Original Research

DOI

10.5594/J08559