1. A method of complementing a spoken text, said method comprising: receiving text data representative of a natural language text; receiving effect control data comprising at least one effect control record, each effect control record being associated with a respective location in said natural language text; receiving a stream of audio data; analyzing said stream of audio data as the stream of audio data is received for natural language utterances that correlate with said natural language text at a respective one of said locations; and outputting, in response to a determination by said analyzing that a natural language utterance in said stream of audio data correlates with a respective one of said locations, at least one effect control signal based on the effect control record associated with the respective location.