DrewBolce,
I am having fun with the foo_dsp_xover plugin now.
Let me paint a picture of my current systems for comparsion. My main system ( I am not allow to fool with it, otherwise my wife will be very mad at me, she loves the sound) is a set of Rosewood Khorns ( with ALK wood horns, JBL tweeters, ALK networks with all Hovland Musicap ), driven by various Mac SS and Mac tube amps or Scott or Fisher or Sherwood tube amps ( nothing fancy or high end stuff ). The sound from the Rosewood Khorns is out of this world, even make my son's heavy rock music sound good.
My other "play" speaker is a set of 1971 KBWO with all stock drivers ( K55V, K77 , BEC AA networks ), the set of KBWO are not in any corners because there isn't any more good corners.
Last month, I wanted to try tri-amp my KBWO without spending a lot of money. I didn't wanted to purchase a hardware crossover box in case I don't like the sound. I will be able to reuse the purchased hardware with a software crossover solution. I picked up a new computer when BestBuy had a sale of eMachine computer ($200), I also brought a Panasonic SA-XR55 6.1 channels HT digital receiver ($150 from Amazon).
First setup, I hooked up the internal 6 channels sound card in the emachine (Hi to SA-XR55 amp, Mid to a HK730 amp, Low to SA-XR55 amp ) to the Khorns. Music player and software crossover is foo2000 with foo_dsp_xover. Installation of foo_dsp_xover was really easy and I was able to play with various crossover setting in no time. Surprisingly, the emachine sound card was not bad, the whole setup have very low noise floor. Sound almost as good as using the stock AA networks.
Next setup, I use a software crossover "Frequency Allocator" from http://www.thuneau.com/ . Same hardware setup without any fancy amplifiers. Thuneau software crossover brings the sound to a higher level, but music is still missing "life" and "emotion". Due to holiday sessons, ususally we have friends and family gathering, I don't want to have wires and amps running over the floors. I haven't tweek or measure the system with RTA yet just by using my ears. This is just my case of proof of concept.
Depends on your goal, if you want to have fun then check out the sofware crossover. If you just want to listen to good sound, buy AL's horn and crossover.