Accession Number:

AD0260458

Title:

A LABORATORY STANDARD SIGNAL-TO-NOISE EQUALIZER

Descriptive Note:

Corporate Author:

OHIO STATE UNIV RESEARCH FOUNDATION COLUMBUS

Personal Author(s):

Report Date:

1960-12-01

Pagination or Media Count:

1.0

Abstract:

An instrument is described which was designed to measure and equate the peak voltage of a word, or the average peak voltage of a group of words, with the rms voltage of suitably filtered Gaussian noise in such a way as to produce a well-defined standard signal-to-noise ratio of zero db. Relative to this zero standard r atio, any practical signal-to-noise ratio may be obtained by adjusting either the noise or the speech channel attenuators. An increase in the attenuation of the noise or a decrease in the attenuation of the speech will have the effect of increasing the signal-to-noise ratio. The important features of this instrument are 1 a panel meter provides a continuous measurement of the Gaussian noise so that during playback or recording of an experimental tape through the laboratory standard, the signal-to-noise ratio may be checked and maintained constant 2 a five-channel instantaneous amplitude-discriminator measures and standardizes the auditory input to the laboratory standard whereby variations in speech-peaks may be checked, and corrected if desired, and 3 both the noise meter and the amplitude-discriminator monitor the operation of the laboratory standard continuously to ensure that a constant signal-to-noise ratio is maintained. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE