Vocal Range and Pitch, and Your Dialect.

Christopher Darden said during the OJ trial African American men tend to have deep voices. I think he was talking about the vocal range of a group. In this case, people who speak with Southern dialect, like African Americans do.

I thought at the time, that's not true. The vocal range of most African Americans, Southern dialect, is high and twangy. Like President Andrew Jackson. People said they could always hear Jackson off in a distance, because he spoke higher.

Vocal range, speaking higher, dialect. How does that all fit together? I can choice to talk in the higher or lower vocal range if I want. And I talk with a Midwestern American accent. Why do people who talk some dialects always seem to talk in one range, like higher if your Southern? Is that a choice? Or does learning to talk a dialect at age 1-2, when you learn to speak with your mouth, forever put your voice in that vocal range?

Does anyone know what I am talking about?