Abstract: The invention is a method for transforming a source individual's voice so as to adopt the characteristics of a target individual's voice. The excitation signal component of the target individual's voice is extracted and the spectral envelope of the source individual's voice is extracted. The transformed voice is synthesized by applying the spectral envelope of the source individual to the excitation signal component of the voice of the target individual. A higher quality transformation is achieved using an enhanced excitation signal created by replacing unvoiced regions of the signal with interpolated data from adjacent voiced regions. Various methods of transforming the spectral characteristics of the source individual's voice are also disclosed.