Procedure "senza vibrato": a key component for morphing singing

A procedure to remove vibrato from singing voice was proposed to enable auditory morphing between musical performances played under different conditions. Analyses of singing samples in the RWC music database using a speech analysis, modification and synthesis system STRAIGHT provided necessary information to implement “senza vibrato,” the procedure that removes vibrato. A preliminary subjective evaluation for artificially adding and removing vibrato indicated that the proposed procedure effectively control perceived vibrato while preserving naturalness of the original singing.