Phonetics - Unit Four - Lesson No. 21
Trask (1996: 336) defines stress as a certain type of prominence which, in some languages, is present upon certain syllables. Stress is variously associated with greater loudness, higher pitch and greater duration, any of which may be most important in a given case, and sometimes also with vowel quality.
Stress in linguistics is the relative prominence of one syllable in comparison to other syllables. It is part of a language’s prosody and helps to break up the speech stream into smaller units. Stressed syllables are either louder, higher and/or longer than unstressed syllables and more resistant to reduction processes (Nancy C. Kula et al (Editors) 2011: 95).
Stress manifests phonetically with one or more correlates. Auditory or perceptually speaking, these are length, loudness, pitch and vowel quality. Acoustically speaking, the correlates are reflected in duration, intensity, or amplitude, fundamental frequency and spectral structure. The use of these correlates is language-specific. English, for one, is said to have pitch as a stress correlate, combined with a preservation of vowel quality in unstressed syllable and a strong tendency to reduce vowels in unstressed syllables. In Modern Greek, …, stress is characterized by a combination of intensity and duration. In German, duration/length seem to be the main cue for word stress (Kula et al 2011: 96).
In order to highlight the phonetic aspects of stress, we will take English as an example. Collin & Mees argue that, in English, four phonetic variables appear most significant as indicators of stress: intensity, pitch variation, vowel quality and vowel duration.