Measuring the Mean Power of Varying-Amplitude Complex Audio Waves

A new instrument which is capable of determining and recording, over successive short time intervals, the mean-power level of complex audio waves of rapidly varying amplitude is presented. While designed primarily for research work with speech sounds, where variations of as much as 35 db in level within 1/ 100 of a second are not uncommon, the unit could be applied to the powerlevel analysis of any voltage wave varying with components fully within the audio range. The apparatus provides a representation of power level in decibels for the brief phonetic elements of speech or for other similar elements of widely varying amplitude, without confusion of data or ambiguity of interpretation.