Bi-amping Rules


I wasn't sure if this question belongs in the amp or the speaker section but I figured I'll post it here. Those of you who have bi-amped your speakers, what's the general rule for deciding which amplifiers are better for low frequency vs. the high frequency drivers. I recognize an accurate answer will depend on the particular speakers and amp combinations but I'm looking for general rules of thumb from personal experiences and not application specific recommendations. For the sake of the argument, let's assume the amps are different but the gains on both amps can be adjusted if that matters. Thanks.
128x128kalali
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@gibalok did you ever try to bi-amp with your VX-5 Twenty?  I have the same amplifier powering my Legacy Focus SEs.  Although it sounds great, I want to experiment with passive bi-amping the bass drivers with a Class D amp.  I do have on order a 7-channel HT amplifier from D-Sonic.  It also has 26dB max gain like the Ayre.  It will be 800w/channel compared to Ayre's 350w/channel, so it's a bit over the 2:1 ratio.  But I'll try it when the D-sonic arrives and if I don't like it for the better, then nothing gained, nothing lost.  It was bought for my center, surrounds and atmos speakers anyway.
I like integrated amps that have pre outs so if needed I can add a muscle amp to drive the bass. I've had a few pair that needed gobs of power to wake up the bass.