what happens if a sub-box don't have like those air holes for the air to get out you know what i mean?

Answer 1

A reflex enclosure is a cabinet without a port. These cabinets have the ability to give a snappy bass response since it uses negative air pressure within the cabinet to return the speaker cone to it's rest position. Since the speaker must act against negative air pressure in it's "throw" more power will be required to get additional low end.

Most speaks today are of the ported design. These speakers use tubes called "ports" of various lengths to accentuate the frequencies that are lacking in the drivers response curve. In my opinion, a reflex cabinet with a bit more than average juice delivery is the way to go.

Answer 2

The air hole is called a "reflex port". In a properly designed reflex cabinet, the total box volume for, say a 10" driver, would be about 2 cubic feet. In fact, almost no manufacturer makes a properly designed cabinet because the buyers want a small box. A sealed cabinet (no hole) will often have smoother sound but will usually be less efficient (need more amp power). If you find a 2-channel woofer with no hole, it may sound fine but need more amp power. If your amp doesn't have enough power, it may distort and send damaging energy to the speakers (all 3).