Formant Frequencies of Adult Speakers of Australian English and Effects of Sex, Age, Geographical Location, and Vowel Quality

Aims: The primary aim of this study was to provide normative formant frequency (F) values for male and female speakers of Australian English. The secondary aim was to examine the effects of speaker sex, age, vowel quality, and geographical location on F.

Method: The first three monophthong formant frequencies (F₁, F₂, and F₃) for 244 female and 135 male speakers aged 18-60 years from a recent large-scale corpus of Australian English were analysed on a passage reading task.

Results: Mixed effects linear regression models suggested that speaker sex, speaker age, and vowel quality significantly predicted F₁, F₂, and F₃ (P = 0.000). Effect sizes suggested that speaker sex and vowel quality contributed most to the variations in F₁, F₂, and F₃ whereas speaker age and geographical location contributed a smaller amount.

Conclusion: Both clinicians and researchers are provided with normative F data for 18-60 year-old speakers of Australian English. Such data have increased internal and external validity relative to previous literature. F normative data for speakers of Australian English should be considered with reference to speaker sex and vowel but it may not be practically necessary to adjust for speaker age and geographical location.