CHAPTER OUTLINE

In this chapter you will learn about the basic concepts necessary for the description and classification of vowels, including: acoustic resonance, excitation spectrum and filtering by resonances, vowel spectra and formants, articulation of vowels, the relationship between vowel articulation and acoustic properties, the differences between monophthongs and diphthongs, oral and nasalised vowels, long and short vowels. The chapter also deals with: vowel systems in the world's languages, vowel instability and variability.

KEY TERMS

1. Cardinal vowel

2. Diphthong

3. Excitation

4. spectrum

5. Filtering

6. Formant

7. Height

8. Lip position

9. Location

10. Long and short vowels

11. Monophthong

12. Oral and nasalised vowels

13. Resonance

14. Spectrogram

15. Spectrum

16. Vowel quadrilateral

17. Vowel system

Introduction

In the vast majority of languages, nearly all syllables include a vowel as their central portion or nucleus. Vowels are sonorant sounds and are produced with a relatively open vocal tract. Vowels are nearly always voiced sounds. This chapter will introduce the basic concepts necessary for the description and classification of vowels, and will begin with a brief description of the main acoustic properties of vowels, including the concepts resonance, spectrum and formant. Also covered are the vowel quadrilateral, cardinal vowels, vowel symbols and diacritics and the distinctions between long and short vowels and between monophthongs and diphthongs. The chapter ends with a brief survey of the types of vowel system found in languages around the world.

Spectrum and resonance

As water is poured into a glass, you can hear a note that gradually rises in apparent pitch as the liquid approaches the top. Why is this? The volume of air above the surface of the liquid in the glass has a resonant frequency.