ABSTRACT
The International Phonetic Alphabet (IPA) suggests that consonants can be uniquely described using the properties of voicing, place and manner. However, these properties do not form a continuum in the same way that vowel height or vowel front-back can be considered a continuum. Although consonants such as stops and nasals have a particular place of articulation that can be accurately described in phonetic terms, how to categorize place for sounds such as fricatives or approximants is much more problematic. Moreover, the role of tongue shape in determining the spectral output for fricative sounds is so poorly understood that it is not at all encoded in the IPA.
The category of consonant manner likewise does not form a continuum of sounds. Whilst it might be possible to say that a stop is lenited to a fricative-type sound at a given location, which in turn might be lenited to an approximant-type sound at the same location, it is not necessarily the case, for example, that a particular fricative such as /s/ or /ʃ/ has a clear counterpart at the stop manner of articulation. Moreover, the articulatory and aerodynamic considerations involved in producing the different manners of articulation – nasal consonants, lateral consonants, stops, fricatives, approximants – result in acoustic outputs that require quite different acoustic considerations for each of the different categories. The fact that these various manners of articulation can form coherent phonological categories is a challenge to phonetic research. This chapter outlines current understandings of consonant articulation and acoustics, by considering some of the previously mentioned issues in greater detail.
