Input acoustic-impedance measurement of the subglottal system

Abstract

The input acoustic impedance looking into the trachea was measured on several laryngectomized subjects. The results show remarkable inconsistency with van den Berg’s data. The subglottal resonances are found at approximately 640, 1400, and 2100 Hz. The acoustic input impedance at the first peak ranges between 25 and 50 cgs acoustic ohms. The results are analyzed by means of a digital simulation based on anatomical studies, and the tract wall impedance necessary to produce the measured subglottal impedance is calculated. Subject Classification: [43]70.20, [43]70.40, [43]35.20.