I dont think so, most HU with pre amp outputs will have front, rear and sometimes sub outs. The front and rear will be full range. You can always get some bass blockers if you need to.
I bought a Eclipse CD7100, does this have it? I been reading the manual, but I'm still not sure. I think the whole time it is referring to the preamp outputs, when it mentions "front, rear, sub" or whatever it states exactly, I forget.
That unit does have xovers so you can adjust the frequency pretty much how you want it. It also has 3 sets of 8 volt outputs.
I think they're 5V preamp outputs, no? Are HP/LP cross-over functions for the high level speaker outputs, though?
I think they are 8 volt but you have the unit so it should say in the owners manual or even on the faceplate. You can set the xover so you only get high frequency signals to your speakers. I think that is what you are trying to do. It should tell you in the manual. What speakers do you have?