Average loudness level, mean fundamental frequency, and subglottal pressure: comparison between female singers and nonsingers.

Subglottal pressure, measured indirectly as the oral pressure during /p/ occlusion, was studied in 10 classically trained female singers and 10 female nonsingers, as they uttered the syllable /pa/ as softly and as loudly as possible over their entire voice ranges. There were no discernible differences between the subject groups for soft vowel phonation, but for the loudest vocalizations the singers used considerably higher subglottal pressures. Possible reasons for this difference are discussed.