No, I don't have them crossed over or anything. I'm just an intermediate audio guy so I don't mess with that kind of stuff much. Just the positive and negative wires running from the receiver to the speakers
If I'm understanding you, you've never played with the crossover?
If that's the case, I'd suggest this may be the reason you feel the bass to be lacking.
If you're worried about upsetting the balance you have now, just mark what setting the crossover is at presently, then play with it and see if you get better results.