Hello dobias ... I'm not sure how you are trying to run your set up ... but in mine I have two outputs on my source Cd (I don't use a preamp ) ... one feeds my main amp and the other feeds the crossover which controls my two subs
My main speakers never see the crossover ... I only use it to tailor my passive sub
If you want to use the crossover for your mains also ... It is a 2 way with a sub out ... so you can still have control/split over your mains's woofer/mid-tweet
Each channel has a Hi and Low out to Bi Amp main speakers and there are a Sub out channels also ... it's actually 3 way when you count the sub out
It should be flexible enough to work in many situations ... but if you are going to run your main speakers through it ... you may want to consider a crossover of higher quality ... you can probably find more transparent units at a much higher price points
Because the original poster was only concerned with low frequency ... I recommended the Super Pro
I only use mine on my Subs and wasn't concerned with controlling my main speakers ... so transparancy wasn't an issue
He is a link to the owners Manuel ... should explain everything you need to know better than I
ATB, Dave
http://img3.musiciansfriend.com/dbase/pdf/man/m_182466.pdf