This study is, to our knowledge, the first to compare the voice quality of several accents of the British Isles. Our hypothesis is that voice quality can vary according to the regional accent of the speaker. The Long Term Average Spectrum (LTAS) was measured for each of the 50 speakers. Then, in order to test our hypothesis, a Principal Component Analysis (PCA) was carried out to compare the spectra. The results showed that at least two accent groups could be isolated from the others. The spectra of the Belfast accent were particularly concentrated around the negative part of the first component. This can be explained by the fact that the Belfast accent is still strongly influenced by the Celtic languages spoken in the region.