Here you go

[a:] words, not that stressed

[o:] words, not that stressed
Father and box are not examples of the american A sound. The A in father is more like the Russian "a" (In fact, that's what the Russian learning textbooks use as an example for Russian pronunciation) and the o in box in between our a and our o.

EDIT: Oh.. wait.. [a:] is exactly what you meant. For some reason I was thinking [ae]
Disregard this.