I grew up 20 minutes from Manchester in Concord, NH, and I have no idea who you were talking to in manchester, but I promise you that there is no "NH" accent.
http://en.wikipedia.org/wiki/New_England_English
"New England English collectively refers to the dialects of American English originating in the New England area. Natives of much of Connecticut, western Vermont, and western Massachusetts, as well as some members of the current younger generation in other parts of New England, tend to speak with an accent that is closer to General American"
So please stop lumping NH in with that shitty ass boston accent. The only people that talk like that are the uneducated dicks moving from other shitty locations.