Abstract
In spoken Czech language, the stress and post-stress syllables in human speech are usually characterized by an increase in fundamental frequency F0 (except for phrase-final stress groups). In unit selection text-to-speech systems, where no contour of F0 is generated to be followed, however, the F0 behaviour is usually tended very vaguely.
The paper presents an experiment of making the unit selection TTS to follow the trends of fundamental frequency rise in synthesized speech to achieve higher naturalness and overall quality of speech synthesis itself.