4-Channel Soundblaster Crossover EQ Software

Ok... I was googling this for the last 1/2 hour and I thought someone here could point me in the right direction...

I've got an old SoundBlaster Live PCI value edition in my PC. The "Front" Speakers is my PA system. Big speakers, decent speakers... My "Rear" speakers are the tiny factory speakers that came with my DELL.

I was wondering if there was a program that would let me assign a certain frequency range to the "Front" speakers and a certain for the "Back". Kinda like Independant EQ's for each channel. I'd hate to have to buy some hardware to put in line when I'm sure somewhere there is software that will let me do this..

Thanks for your help,
-MMFAN-