Persuasion of voices: The effects of a speaker's voice characteristics and gender on consumers' responses

Voices are present in most communications. Yet, the literature on voice persuasion is astonishingly limited and fragmented, focusing on certain voice characteristics (e.g. pitch), contexts, and providing mixed results. This research attempts to integrate the various constructs and mechanisms involved in voice persuasion as a result of the cross-fertilization of the disciplines having studied voice (psychoacoustics, cognitive psychology, anthropology, psycho-sociology, marketing, and politics). Study 1 manipulates via acoustic software the key voice characteristics (i.e. pitch, roughness, and brightness) and gender of a speaker heard in a radio advertisement for a neutral, non-gendered product category. Study 2 explores a potential boundary condition of the effects of voice, the presence of context-specific expectations toward the speaker (i.e. gender and competence level), by manipulating the voice of a political candidate. The effects of the voice characteristics are consistent in both contexts: speakers with low- (vs high-) pitched, dull (vs bright), and smooth (vs rough) voices are the most effective. Speakers with high-pitched, dull, and smooth voices are perceived as the most competent. Finally, speaker gender plays a secondary persuasive role; listener gender only plays a role in the absence of context-specific expectations toward the speaker. Implications for voice and speaker persuasion as well as for voice casting and coaching are discussed.