Abstract: There is disclosed a method and apparatus for providing signals for a synthetic voice by way of derived voice-representative data. In embodiments of the invention, the derived data is derived by combination of data representative of first and second (and maybe more) voices of a base repertoire, the combined data including selected parameters of a formant-type voice synthesiser. Combination may take place by interpolation between or extrapolation beyond the voices of the base repertoire. Individual parameters within the derived data may contain different proportions of corresponding parameters of the base repertoire. The invention is applicable either directly to control parameters of a synthesiser or to tables for these parameters.