An analysis of Norwegian vowels: What determines the topography of a vowel space?

Abstract

Paucity of information on the acoustic structure of Norwegian and interest in comparing similarities and differences with its well-described neighbor, Swedish, led to an investigation of Norwegian vowels. A commutation set of single-word utterances was presented to 12 native speakers (4 male, 6 female, 2 children), yielding a corpus of 505 tokens. Spectrographic analysis guided measurement of each vowel’s first five formant frequencies both at a single point in steady state (single FFT) and throughout (overlapping FFTs) to exploit the varying fundamental frequency through the steady state, which affords a more accurate reading of the formants. Results indicate a pattern of formant convergences and attenuations in the range of the first four formants, a robust finding which falls between the cracks when using a standard F1/F2 technique for laying out vowel spaces. That such patterns characterize different vowel categories and dimensions (front–back, rounded–unrounded) opens discussion to more general questions of what determines vowel location in acoustic space [e.g., Lindblom (1986)]. The hypothesis that two languages with isomerous vowel categories will yield unique acoustic topographies when their systems are structured on different primatives/‘‘features’’ is discussed.