i have a 15 eclipse titanium in a ported box tuned to ~35 Hz and when i play low frequencies like in the 20 Hz area and below i get very little excursion, like 1/4-1/8 inch. shouldn't be getting a lot more. i am powering it with a audiobahn a18001dt which claims 1200wrms @ 2 ohms and i have a panasonic CQ-7401 hu. could it be my hu that has a low frequency cut off or could it be i am underpowering the sub because it is a 1500wrms sub?