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
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Bob, Vandersteen recommends taking the imput impedence ( 22 kohm) and doubling when running balanced = 44 kohm. When I split the cable coming from the xover to both channels is the xover seeing 44 kohm & 44kohm which would be the total 88 kohm for the amp, or are you saying the total will stay 44 kohm so each channel becomes 11 kohm x2(11 in 11 out balanced) =22 kohm x2( boyh channels) = 44kohm? The M5-HP can be set at 20k, 33k, 50k, 75k, 100k, 150k, 200k, 300k and 400k.
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