Do you know someone who’s a loud talker? They speak so loudly everyone in the restaurant can hear them. While other people are so quiet, it sounds like they’re in a library. Why is that?

Well, several factors affect voice volume. Here are the facts, from Dr. Amee Shah, director of the speech acoustics lab at Cleveland State University.

• First, how you’re built affects loudness. People who have bigger larynxes and thicker vocal cords naturally speak louder. That’s why most male voices are louder than female voices. And quieter people sometimes have smaller lungs, so they can't generate enough airflow for a louder voice.

• Loudness also depends on age. As we get older, our vocal cords get stiffer, and don’t vibrate as fast, which makes our voices quieter.

• Another factor: How you’re raised. If you grew up in a large family, or around the hard-of-hearing, you probably learned early on to speak up if you wanted to be heard. But sometimes people raised in loud houses go the opposite direction, and become quiet and withdrawn.

The good news is you can definitely train yourself to speak more loudly. Practice taking deeper breaths. And learn to use your diaphragm, like a singer. The more air you expel, the louder you’ll speak.
But it’s trickier if you speak too loudly. Most loud-talkers have no idea that they’re being loud, unless somebody tells them because they’re too busy focusing on what they’re saying instead of how loudly they’re saying it. So, if you want to lower your volume, ask your friends and family to tell you when you’re over the top, and you’ll eventually get the hang of it.