This paper describes the work with F0 and segment duration when developing a prototype system for analysis of speaker age using data-driven formant synthesis. The system was developed to extract 23 parameters from the test words - spoken by four differently aged female speakers of the same dialect and family - and to generate synthetic copies. Audio-visual feedback enabled the user to compare the natural and synthetic versions and facilitated parameter adjustment. Next, weighted linear interpolation was used in a first crude attempt to synthesize speaker age. Evaluation of the system revealed its strengths and weaknesses, and suggested further improvements. F0 and duration performed better than most other parameters.