Mastering your public speaking voice power can seem the most difficult to master of the three P's.
To best understand, think of the time when you have heard someone screaming. The untrained voice is not able to maintain stability when excess power is used during speaking (or screaming). However, the same human voice can sing in a dynamic range and maintain the audible tonal qualities.
The Secret of The Public Speaking Voice Power
Here is the secret of power.
Singers know that the voice should come from the diaphragm. Most speak from the upper chest to as high as the throat.
How Low Do You Go
Stand in front of a mirror. Start talking or practice a talk. As you speak try to imagine that your voice is originating at some point between the middle of the nose and the bottom of your lungs where the diaphragm resides. If abstract thinking does not come easy this may not be possible.
Once you have a mental picture of the place your voice originates, start to lower the origin of the voice.
This will create a challenge. The lower you go the less power you will feel you have over your voice. Do not confuse a lower tonality with power. The voice will indeed go lower for some. The power will also drop.
This is because of a lack of training and lack of use. Learn to use this part of your lungs and the power will follow in short order.
Once you make it a practice of speaking lower in your chest, try to increase the tone. This is accomplished through the vocal cords. Just as a tense, stressed out speaker will have a high tonality in voice quality, when speaking from the diaphragm, the exact opposite happens. It becomes lower.
It becomes hard to speak in a higher tonal voice and maintain dynamic range of clear audible speech. However, try to sing in a higher tone and it is much easier.
Even if you have a voice that would get you thrown off American Idol, singing is a good tool to learn to mastery of your voice. The more you get to know your limitations and extend them the faster you will become a dynamic speaker. Unlike singers, speakers can have greater latitude with their voice quality and still be acceptable.
Go to Dynamic Range Page and learn how to put this all together.