Acoustic Variability of Vowels in Greek Spontaneous Speech

To date numerous studies have investigated the acoustic characteristics of vowels produced in isolated words or other well-controlled types of speech material in several languages. However, relatively limited research has been carried out for vowels produced in spontaneous speech. In addition, relatively limited data are available for vowels in some languages, such as Greek. The aim of this study is to investigate acoustic variability during the production of the 5 Greek vowels /i, e, a, o, u/ in spontaneous speech. Data were recorded from two Greek male speakers producing a monologue. Formant frequency and duration measurements were made for all vowels produced in consonantal contexts. The study examines the extent of acoustic variability present in the data and some of the factors that contribute to such variability, including duration and context. Results show extensive variability for all vowels and the presence of overlapping formant distributions especially in the central part of the vowel space.