Bi-amping with 2 2ch amps


I have one Pass X-150 and want to bi-amp.What is the best way to go about this staying with 2 X-150's. My pre is a Pass X2.5, speakers are vandy 3a sigs w/2 2Wq's. Thanks for any imput !
samhar
Vertical biamping. Hook up the highs of one speaker to one pair of amp outputs and then hook up the lows for the same speaker to the other pair of outputs on the same amp. So you have each amp powering one full speaker. Should sound great!

Arthur
This article has info on vertical and active bi-amping: (http://www.soundstage.com/synergize/synergize031998.htm)
Thanks to both of you!! Vertical biamping is exactly what I was wondering about. I have Vandersteen X overs for the subs are they best near the pre or the amps, the run is 10'. Also would it be best to split at pre or amp , if cost wasn't a factor?