Variation and change in thetrapandstrutvowels of RP: a real time comparison of five acoustic data sets
The present study examines evidence for change in real time within the short vowel subsystem of the RP accent of English over the course of the twentieth century. It compares plots of average formant positions for the short vowels, stemming from several data corpora. It furthermore describes a change over time in the juxtaposition of thetrapandstrutvowels as captured in the calculated angle and distance between the two, usingtrapas a fixed point. This representation of a relationship in a single measurement by means of angle calculation is a methodological innovation for the sociophonetic enterprise. A value specifying the geometric relationship between two vowel positions is precise and replicable, as well as abstract enough to be comparable across data sets. Differences between ‘phonetic’ and ‘sociolinguistic’ stances on the interpretation of acoustic vowel data in formant plots and the issue of suitable vowel normalisation procedures for sociophonetics will also be discussed.