Yeah, the difference in a cross-over and an eq is that the cross-over sends varable signal to your amp. For example you have control on your subs and 4channel up front and you can decide you want 80hz and below going to your sub and 80hz and above going to your 4channel.....or you can raise it or lower it at will. These are awesome because amp cross-overs are usually either on/off or vary hard to tweak since they rarely have notch notation as to where you are on that frequency curve.

And EQ will allow you to fine tune the frequencies going to your amp. I have a Rockford Fosgate OEQ1 I'll sell to you if you want it. $25 with shipping