I have a kicker 700.5. Deck is kenwood. It has sub vol adjustment on it. Now, do I turn gain down on amp and use deck to up sub volume. Or turn deck down and use gain on amp? Have two audiobaans in slot vented box. Just don't hit to hard. 10" aw100t's put a kicker l5 factory vented box into try and just too harsh. Ajustment?