Speaker modification with LPC pole analysis

Speaker modification is the ability to change the perceived speaker identity of a recorded utterance. Basic to this is the capability to alter the vowel segments of speech. Not only do these segments comprise the majority of the voiced portion of speech but they are dominated by clearly defined acoustic parameters-formant frequencies and pitch. A method of altering the formant frequencies of vowel segments using LPC analysis/synthesis was investigated. Pole location modification based on statistical references provided individual control over formant frequencies and bandwidths but, in some transformations, lead to artifacts in the reconstructed speech