In this TED talk sound expert and public speaking coach Julian Treasure outlines how to effectively use your voice to deliver a message and make people want to listen to what you have to say:
While of course regarding a complex subject like skillfully using your voice and speaking in public effectively such a short video can by no means be comprehensive it gives a good idea about the key ingredients of getting your message across.
In a larger context, Julian also briefly broaches the wider subject matter of not only communicating clearly but also listening intently in a medium consciously designed for understanding each other.