OP Eriks solution is a great way for around 150.00 or so.
I've used Dayton's.
I currently use Behringer DCX 2496, as an active XO for bass management.
WHY? here is the deal for bass drivers and dampening to work (overshoot). The amp has to be directly coupled to the drivers. NO passive XO. Anything between the driver and the amp including long or small speaker cables.. This is where Heavy copper and short runs are your friend..
Once you clean up the BASS mess, correctly, everything else will work perfectly with passive crossovers in the mids and highs..
300 hz and down.. is alway a mess. I've tried and still have GRs OB servo system. To tell the truth my Behringer set up is better.
It will control 6 amps for 6 bass units.. I use MB columns and med large double driver passive subs. (4.5 QF).
Full blown active DSP, daisy chainable, threashold, time delay, at least 20 types of XO from 1-4 order, summation for a third channel, mic tap for laptop visual and correction.. OTF correction.. 300.00 usd.. NEVER had one fail.. BTW there is a guy that will hot rod the heck out of one, for about 1K..
15-20 years now.. Serious piece of very flexible gear.. Great for building Passive XOs too.. It's what I use..
Time to feed the chickens..
Regards