I just have a question about 4th order boxes. I see lots of installs with them and I hear (and read) that they're good to use for the lows. But what I don't understand is how they get low if the lows are coming from the sealed chamber. Sure sealed box's can get low, but usually a lower tuned ported box has better low end extension. So whats the difference between a sealed enclosure and 4th order when it comes to the low bass?