ampeg svt4-pro, bi-amping?

[bassman_2_1]

hi i am currently using an svt4-pro with and ampeg BXT115"-hl and BXT410"hl both 4 ohms cabs. bloody hell this setup really ace! But any users used the bi-amp function on the amp with this combination of speakers? i really wanna try and get an even punchy bass end (like flea), i know he also uses his stack bi-amped? as the svt4 offers a crossover control i am not too sure where or what frequcies i should start pumping into what speakers? would i be better getting a separate crossover unit? or is any1 using the crossover on this amp and satisfied ? cheers