1. An apparatus for text-to-speech conversion comprising: a neutral duration prediction block comprising computer hardware configured to generate an emotionally neutral representation of a script, the emotionally neutral representation comprising a neutral duration associated with each of a plurality of phonemes; and a duration adjustment block comprising computer hardware configured to apply a duration adjustment factor to each neutral duration to generate a transformed duration sequence, the duration adjustment factor being dependent on an emotion type and a linguistic-contextual identity of the corresponding phoneme; a neutral trajectory prediction block comprising computer hardware configured to generate a neutral fundamental frequency (F 0 ) prediction and a neutral spectrum prediction for each adjusted duration of the transformed duration sequence; and a trajectory adjustment block comprising computer hardware configured to apply an F 0 adjustment factor to each neutral F 0 prediction and a spectrum adjustment factor to each neutral spectrum prediction to generate a transformed representation, each of the F 0 adjustment factor and the spectrum adjustment factor being dependent on the emotion type and the linguistic-contextual identity of the corresponding phoneme.