I don't know that I'd talk of "command voice" as much as "command presence". Let me elaborate here:
Some people have that booming voice that commands attention whenever you speak to them. One officer who works for me is that way. He could be telling you about his miniature poodle's favorite squishy toy, and he'd still sound like a drill instructor taking control of a bunch of recruits in basic training. On the other hand, some people just don't have the "voice" needed to sound commanding on its own, and they can sometimes sound ridiculous when they try to sound commanding. I have another officer I've worked with who is like that. This guy is a legitimate tough-guy, and a great cop. Very few people would want to get in a fight with him, and those who did haven't ever prevailed in my presence. But, he has a voice that doesn't exactly command a ton of authority, and when he tries to make his voice sound commanding (which he does) I almost laugh every time. You know who else sounds very unconvincing based on their tone alone? Mike Tyson. I wouldn't want to get in a fist fight with him, either.
Regardless, we all have the voice that we have. But, you can still give off a commanding presence, because a command presence involves much more than just voice itself. It's a combination of posture, eye contact, what you say, how you say it, and how you carry yourself. It's an issue of overall confidence that convinces an opponent that you're not someone they want to tangle with. It does make a difference, and if you watch any rookie cop handle an intense situation when compared to a veteran officer, you'll immediately see the difference (and it's a dramatic difference). In other words, it's an issue of confidence that should be seen in the entire way you handle a situation: calm, cool, collected, forceful, controlled, and in control. It's what you say as much as how you say it, and it's how you say it as much as what you say.
