Polder dutch: aspects of the /ei/-lowering in standard dutch

This paper is an initial report on the systematic analysis of changes within the vowel system of Standard Dutch. The work focuses on the recent lowering of the diphthong /Ei/, known as ‘Polder Dutch’ (Poldernederlands). The purpose was to find an automatizable method to reliably analyze and compare speakers of a large corpus of Dutch spontaneous speech. Diphthong variants of twelve native speakers were compared by measuring both formants and spectral energy distributions. The resulting pc1-pc2 plane of a principal component analysis (PCA) on the barkfiltered spectrum of anchor vowels /a/, /i/, /u/ was comparable to the F1-F2 bark plane of the same segments and explained 90% of the variance in the data. The differences between the speakers’ vowel spaces appeared not to depend on sex, so male and female data could be calculated within the same analysis. The distance of the diphthong /Ei/ to the anchor vowels in the pc1-pc2 plane, together with the dipthong dynamics were the major cues to diphthong quality. Further indication of a sound change in progress for the ‘Polder Dutch’ speakers was the position of /E/ in the vowel space.