In Norwegian and English, as in many languages, vowels can be characterized in terms of distinctive phonological vowel quantity and vowel quality. Norwegian is described as having a phonological distinction between long and short vowels, whereas in English vowel quantity is generally seen as more distinct. However, both vowel quantity and quality can acoustically be realized in vowel duration and the accompanying characteristic resonance of a vowel. The goal of this project is to examine the perceptual weight of vowel duration and the first two formant frequencies for Norwegians when hearing Norwegian vowels versus English vowels. Six sets of words were resynthesized based on three Norwegian vowel pairs and three English vowel pairs. The words in each set were resynthesized using the members of the pair as the end points of a matrix with five degrees of vowel duration and five degrees of F1 and F2 adjustment. Based on judgments by native Norwegian listeners, results to date suggest that native listeners of Norwegian will be more perceptive to differences in vowel duration than to spectral characteristics. Results for the English and Norwegian vowels will be compared and discussed in terms of native language influence on vowel perception.