> A vocal timbre can also reveal economic and cultural background. Some singers...were encouraged to either accentuate their timbre...or to abandon what occurred naturally for them

Vocal timbre is a big identifier of different rap subgenres and artists, seems like. Certainly seems like much of the vocal delivery on a track explores fluctuation of the timbre, even when the pitch is constant or has little dynamics.

It's interesting to think how the timbral effects of a regional accent would interact with the beat construction/development. Is the trap hi-hat a result of the Southern drawl?