I think every Dom/me has a Voice with a capital V. Whether it's their normal voice, or a voice they only use on their submissive, it's distinctive and instantly recognizable. It's rarely a raised voice, it doesn't need to be loud. In fact, I find it much more effective when used quietly, even whispered, and in close proximity to the sub. It's low, direct and focused, and it expects to be obeyed.
I think of it like the Voice the Bene Gesserit priestesses use in Dune. Not to get all super-nerd, but I always found that to be the most compelling aspect of their training. When I trained as a Pro Domme, I saw the other Mistresses using what seemed to me to be the Voice on clients. It was instantly familiar to me, and I recognized the power of it immediately.
Daddy would use his voice to command, tease, threaten, instruct, encourage, and discipline me. Sometimes it wasn't even the words he chose, but the tone of his voice that would send the shivers down my spine. All I would have to hear was "Laani..." or "Little girl..." and I could tell if I was in trouble or being praised.
M doesn't like his voice. He says it's nasally, but I like it. I like the awe with which he says "You're so pretty," or "You don't even know how gorgeous you are, do you?" Or the desire that lowers his voice when he says "Take off your clothes." And the soft vulnerability that shades his pleas when I force him to ask for the kinky things he wants me to do to him.
M claims he can't talk dirty. That he can't think of what to say, and that he'd be too embarrassed to say such things. But I don't think it much matters what he says, it's the way he says it that thrills me. I don't care if he whispers, growls, gasps, or murmurs...Just give me that Voice.