I have 2 brand new Alpine dvc4ohm 12"s in ported box, each chamber has 1.35 volume. amp is hifonics gladiator 1800x1 and subs are wired to 1 ohm. I set gain on amp with DMM to 42.24v and system was not loud at all. headunit volume is 35 of 50 on sony HU.... so I turn up settings on amp to get...