The Perception of Vocal Traits in Synthesized Voices: Age, Gender, and Human-Likeness

As computer-generated voice synthesis has become a significant part of communications between computers and people, there is a need to understand the role of paralinguistic attributes of the voice, such as age, personality, and gender. In many cases, the synthesized voice is produced by concatenating segments of recorded human speech, which can be experienced as a lifeless voice that lacks free expression and fluidness. Technology companies have been developing their own unique synthesized voice identities without paying attention to the stereotypical traits being heard. This study evaluated the responses of 18 listeners who were asked to consider the paralinguistic traits of age, gender, and human likeness from 13 voices in IBM’s Watson corpus. The results of this study were similar to a previous study, with no voice achieving complete human likeness, no voice being perceived within a single age frequency band, and none tied solidly to their given binary gender.