Nonlinear speech synthesis

This paper examines the how and the why of nonlinear speech synthesis. It discusses why nonlinear speech synthesis should be considered, reviews the recent history and describes in detail a variety of approaches to the problem. It argues that while modern concatenative speech synthesisers produce speech which is intelligible, however they are very inflexible and often lack a human quality. The paper does not suggest that nonlinear speech synthesisers are ready to replace conventional approaches, but rather that they offer some potential advantages but there is a considerable amount of research still to be carried out.