Complex Vowels in Persian: An Acoustic Investigation

Acoustically, vowels are composed of a target (steady state) and formant transitions in the context of consonants. Targets represent the fixed configuration of the vocal tract during the production of vowels, while formant transitions represent the movement of the vocal tract from the production of a consonant to a vowel and vice versa. Targets and formant transitions are present in simple as well as complex vowels. Complex vowels, however, have a more complex internal structure and can be classified accordingly. The internal structure of complex vowels of Persian was investigated in open stressed syllables produced by 14 female and male speakers using the method proposed by Lehiste and Peterson (1961). Results showed that complex vowels are of two kinds in Persian: single-target and double-target. The members of this latter group can properly be called diphthongs.