If you want your subs to hit harder, there are a few things you can do. First, make sure they're properly powered. If your subs are underpowered, they won't be able to hit as hard as they could if they had more power. Second, use low-pass filters to allow only the low frequencies through to your subwoofers. This will help them reproduce the low frequencies better and make them sound louder and punchier. Finally, experiment with different EQ settings until you find something that sounds good to you.