*shrugs* Like any race, I'd imagine different dragons sound different. But going on their race characteristics, "ferocious animal" isn't really a defining trait.
I heavily disagree, the single most defining characteristic of dragons is that they're ferocious animals. Huge monstrous fire breathing and savage animals, that bring fear into the hearts of every man, they burn villages from above, live in crags and rocky mountains and their favourite pasttime is to snack on people.
The whole intellectual dragon that can also turn into a human, cast spells, sounds like a british professor and play nice deal didn't come into play until D&D with metallic dragons.