Vowel Formants and Angle Measurements in Diachronic Sociophonetic Studies: FOOT-fronting in RP

This paper examines vowel formant data from a corpus of recordings of male speakers of RP born during the course of the twentieth century. It compares average formant positions in the F1/F2 plane for the short vowel FOOT in juxtaposition with LOT (for this Keyword notation see Wells [12]). The relative positions of the two vowels are represented by a single numerical value, which is the calculated angle from LOT to FOOT relative to the vertical. Changing angle values between the early and the later part of the twentieth century reflect a diachronic process of FOOT-fronting and unrounding which is well documented in varieties of British English, such as Torgersen and Kerswill [10], including RP, as in Hawkins and Midgley [6]. The paper also demonstrates the versatility of an angle calculation method (Fabricius [3]), used in combination with F1/F2 plots, in producing replicable quantified measures which demonstrate changing vowel juxtapositions in real time.