Phonation Duration And Optimum Frequency

Abstract

Optimum frequency is considered to be the frequency at which maximum physio-acoustic economy is achieved. The purpose of this study was to find out the acoustic economy, at optimum frequency, as determined by an objective method of locating optimum frequency. The acoustic economy was measured in terms of the maximum duration for which the subjects could sustain phonation at a particular frequency. The maximum phonation duration at optimum and at frequencies higher and lower than the optimum frequency were measured using a stop-watch. 15 male and 15 female adults were asked to phonate vowel /a/ as long as possible keeping the frequency and intensity constant. The maximum phonation duration at optimum, + 100 Hz, + 200 Hz, + 50 Hz and - 50 Hz from the optimum were determined. The results showed that the maximum phonation duration at optimum frequency was significantly longer than at other frequency levels. Therefore it was considered that there was maximum acoustic economy at optimum frequency, as determined by this method.