Topic-141: Summary of Vowel Quality In this course, we have discussed many features related to the description of vowel sounds. In this topic, we provide a summary of all these features related to vowels. There are two features of vowel quality (i.e., height and backness of the tongue) that are used to contrast one vowel with another in nearly all languages of the world. But there are four other features that are used less frequently and not all languages exhibit them. They include ‘lip-rounding’, rhotacization, nasalization and advanced tongue root (ATR). The following are the acoustic correlates of all these six features • Height - frequency of formant one (inversely related to F) • Backness - difference between frequencies of F and F • Rhotacization - frequency of formant three • Rounding - lip position (rounded, half rounded or neutral) • ATR - width of the pharynx (ATR or RTR) • Nasalization - position of the soft palate
