Sound level variation findings for pianissimo and fortissimo phonations in repeated measurements

Ten vocally untrained female university students vocalized /a:/ at five given pitches within the average female speaking range (196, 220, 262, 330, and 396 Hz) as softly as possible (pianissimo) and as loudly as musically acceptable (fortissimo). To study the repeatability of voice range profile (sound level) measurement, the procedure was repeated 10 times in each of the five sample sessions during the day, in connection with vocal loading that included five oral readings (45 min each), 15-min pauses, and a lunch break (45 min). A sound level meter specially designed for voice range profile measurement was used. The effect of the loading was seen on the mean sound level changes and intraindividual variation on SDs. The difference between the first phonation and best performance indicates significance of the repetition of the measurement. The sound level averaged across the pitches rose significantly during loading. The intraindividual SD varied between 3 and 4 dBA according to pitch and loudness, and the sound level difference between the first phonation and best performance was approximately 5 dBA in pianissimo and approximately 7 dBA in fortissimo.