I am kicking around the notion of building a D3 for a center channel next week. I have seen a couple of different options of these speakers. I am thinking of using the plans from speakerbuilder.net but possibly modifying them. Sinse this will be used as a center channel, does anyone know what the effect will be if i raise the tweeter towards the top? I am also thinking of putting the vent on the front underneath of the tweeter.