Voice manipulation

Voice Manipulation was the supernatural ability to manipulate the auditory features in one's voice such as pitch, tone and volume to make it sound different, mostly with the intent on decieving, confusing or threatening.

Examples

 * Vengeance Demons Halfrek and Anyanka each had altered voices at one time. Halfrek used a deepened voice when confusing Xander with a victim and Anyanka had a hoarse, raspy voice when confronting Rupert Giles in her created Wishverse.
 * During her phase as a dark witch, Willow Rosenberg briefly deepened her voice while darkening her eyes while saying "well I've gone pro" to Giles. She later screeched at a high an inhumanly high frequency when on the hunt for Jonathan Levinson and Andrew Wells. Andrew himself said the sound "kills". Also, when the First possessed Willow while she was preforming a locator spell, the First manipulated her to say he wanted her to and in a loud, deep voice.
 * The poltergeist Maude Pearson lured Cordelia Chase into her haunted apartment by prefectly imitating Angel's voice on the phone.
 * When Cordelia was possessed by Jasmine who took on the alias as the Beast's unseen master, she used a loud male voice to pester Angelus and as part of her disguise.