It's important to keep in mind when reading these reviews that the star ratings have to be taken in context. You may recall my review of Lost Universe. That dub was certainly among the poorest I've ever heard, yet it earned two stars, due primarily to the fact that the anime itself was so laughably bad. The anime and dub combined for a camp effect that made me laugh. So while a dub of that quality would get only a single star for almost any other anime, for Lost Universe, it received two. Context, you see.
Something similar is true of ADV's dub of Nadia. I searched for the better part of a day to find the best adjective to describe my impression of this dub, and I finally hit upon "unpolished". The three primary characters in Nadia are all children. ADV took the uncommon step of casting actual children to play the roles. Understandably, there is an air of inexperience in their performances. They rarely nail their lines, though they rarely miss them by much. Their voices stand in contrast to the more experienced performances delivered by the adult actors.
But it works. The end result is a dub with an aura of innocence to it, sort of a "Saturday morning" feel. It's not a sophisticated dub by any means, but it fits perfectly with Nadia's brand of light-hearted adventure. It's all about context.
Let me start with Jean, because how you react to him will play the biggest role in determining whether or not you like the dub. Jean has an accent. It's supposed to be French, but is really just "Jean." When I first heard his accent, I found it annoying. But by the second episode, I'd gotten used to it, and after eight episodes, I can't imagine Jean without the accent. Nathan Parsons (age 12) does an excellent job of portraying Jean's optimism and determination, without ever letting him sound more mature than the boy he is.
Nadia, played by Meg Bauman (age 14), is the hardest of the child voices to review. While I was fairly certain that Jean and Marie were played by children, I was less sure of Nadia. Bauman's voice is sufficiently mature that I wouldn't have been surprised had she turned out to be over eighteen. Her Nadia is a bit grating at first, a little bit of a bitch, but that's in line with the character.
And then there's Marie, played by Margaret Cassidy (age 11). All Cassidy has to do is play a little girl (which she is, although 11-year-olds don't like to be called that), and be cute. Cassidy truly shines in the scene where Marie describes the murder of her parents, breaking into tears. It's utterly believable, and a tricky scene for any actress to pull off, much less one who is eleven.
Grandis Granvar is the leader of the pesky band of jewel thieves who menace our heroes in the early episodes. Sarah Richardson, who has some experience in playing mature villainesses, plays Grandis. (For example, she was Kali in the aforementioned Lost Universe dub.) It's a distinctive voice, over the top with confidence, allowing her to play the dual role of villain and comic relief. It makes her all the more humorous when things go wrong, which they always do.
Anyone has watched a lot of ADV dubs should recognize the voices of Granvar's henchmen Hanson and Sanson, played by Corey Gagne and Martin Blacker (Joe Saeba in City Hunter). Blacker's goofy character voice is especially recognizable, as he's played bit parts with it in several ADV dubs. There's no depth to these performances, but there doesn't need to be. Hanson and Sanson are, at least at this point in the series, pure comic relief. All that is required of Gagne and Blacker is to have good, funny character voices and they pull that off admirably. It's another aspect that lends itself to that "Saturday morning" feel -- Granvar and co. reminded me quite a bit of Team Rocket.