Why a phenomenology of vowel sounds is needed Dieter

In the literature, there is an extensive and often controversial debate on the primary acoustic and perceptual cues of vowel quality, resulting in two main viewpoints that these cues are contained in either the formants, or, alternatively, in the spectral shape. However, in our understanding, one aspect is highly underestimated: the fact that any spectral representation of vowel-quality is directly or indirectly pitch-related. Hence, a given formant pattern as well as a given spectral envelope is in many – if not all – cases ambiguous in terms of representing sounds of different vowel qualities, if speakers equal in size and gender produce the sounds on very different pitches. Neither of the two above-mentioned viewpoints can account for this issue, however. – The present paper (i) summarises the ongoing debate, (ii) describes the empirical evidence for pitch-related spectral representation of vowel quality, (iii) concludes that existing approaches to determine the acoustic cues for vowel quality do not account for all recognisable vowel sounds, both conceptually and methodologically, and (iv) argues for the need of a phenomenology of the acoustics of vowels in terms of building up large-scale, language-specific sound descriptions, addressing all variations of production parameters and their possible extension relevant for perceived vowel quality.