The Secret to an American Accent: Resonating in the Middle

Everyone,

I found a somewhat dated (2000) article on the web which tells the story of a guy from Slovakia living in the US who was trying very hard to acquire an American accent, but despite sounding very close to native, there was still something preventing him from achieving this goal.

Then, he had a major breakthrough when he discovered that American English is "resonated in the middle of the mouth" whereas other dialects are "resonated" in other parts of the mouth, such as in the back of the throat.

I have no idea what this means and I'm wondering if anyone can explain what this article is about.

Here's the link to the article:
http://everything2.com/title/the%2520top%2520secret%2520of%2520talking%2520like%2520an%2520American

Thanks

It's interesting, but I don't know. I think probably only singers know how resonate in the different part of your mouth. Hope someone here can give a hint, that will be great!

Here's another website/video that discusses this:

http://www.expertvillage.com/video/107642_new-york-dialect-placement.htm