The key to making a good speech to the troops or a truly impactful pitch to a client lies in speaking with emotion without being overwhelmed by it. One way to do this is to ensure that the level of passion that you put behind your words isn’t so great as to overwhelm the message you’re trying to convey.
Another is to speak with a measured and strong tone that never rises to the level of becoming abrasive or domineering.
Read the full article here: http://www.fastcompany.com/3060916/five-ways-to-speak-passionately-without-getting-too-emotional