Microphone, Head Contact M-123( )/U

摘要

Work performed during the quarter beginning June 1, 1964 and ending August 31, 1964 toward development of a practical head contact microphone is discussed. Final designs of two transducers to be used in contact location research are described. Preliminary head contact measurements revealed wide ranges of signal levels available at the skull, and indicated a need for increased transducer sensitivity. Redesign of both transducers was undertaken, and the modified inertial unit was used in contact location studies. Location data was obtained at a number of head positions and with two talkers. Overall level variations of about =8 db were obtained. Spectrum analysis of the data was begun, and indicated considerable changes in spectrum as a function of location. (Author)