Studies on the role of 'given' and 'new' information in speech communication normally concentrate mainly on prosodic aspects like duration and fundamental frequency. Except for one study, no significant differences between 'given' and 'new' words are found. In our study we included, unlike the other studies, spectral measurements together with duration and F0 for vowels occurring in (the same) 'given' and 'new' words, in read sentences and in conversation. A significant difference in distance to the centroid and in F0 could be demonstrated between 'given' and 'new' in conversation, but for duration no significant effects could be observed. Whether the spectral differences play a role in perception too, is subject of further research.