Mechanical Reversed-Bias Light-Valve Recording
Many methods have been applied recently for increasing the volume range of recordings. Some, such as the push-pull system, require mechanical and electrical modification of existing apparatus in order to utilize their advantages. In an effort to produce prints capable of standard reproduction, with increased signal-to-noise ratio, the mechanical reversed-bias method has been used at the Twentieth Century-Fox Film Studios. Briefly, it is a method of reverse-biasing a valve so that the valve aperture is increased by the biasing current to a degree sufficient to prevent clash. Further modification provides for a combination of standard biasing up to a certain percentage of modulation and mechanical reverse-biasing from that point on, resulting in an increase of 8 to 12 decibels over the usual methods in signal-to-noise ratio.
- Print ISSN
- 0097-5834
- Published
- 1936-02
- Content type
- Original Research
- DOI
- 10.5594/J08712