Charismatic leaders use voice based on two functions: a primary biological function and a secondary language and culture-based function (Signorello, 2014). In order to study the primary function in more depth, we conducted acoustic and perceptual studies on the use of F0 by French, Italian and Brazilian charismatic political leaders. Results show that leaders manipulate F0 in significantly different manners relative to: (1) the context of communication (persuasive goal, the place where communication occurs and the type of audience) in order to be recognized as the leader of the group; and (2) the elapse of time (from the beginning to the end of the speech) in order to create a climax with the audience. Results of a perceptual test show that the leader's use of low F0 voice results in the perception of the leader as a dominant or threatening leader and the use of higher F0 conveys sincere, calm, and reassuring leadership. These results show cross-language and cross-cultural similarities in leaders’ vocal behavior and listeners' perception, and robustly demonstrate the two different functions of leaders’ voices.