Well I just got AOTC and I am just about fed up with my FIXED receiver crossover setting which is at 540hz. The problem was I was hearing Natalie Portman's voice coming from the tempests which is not good. So my solution was to use the high pass 125hz filter on my PE #300-794 plate amps. I have 2 tempests so I'm using one for each main... I assume this is the best way to wire the dual subs as I have them stereo positioned. My question is if the high pass 6db 125hz crossover is fixed.. then that means I only adjust the variable 40-160hz low pass crossover? Is there anything wrong with stereo subs playing 125hz? I don't know if I want to set the crossover that high but it's probably a lot better than a 540hz crossover point! I think it would actually be ok with the 125hz because the subs are each placed next to each main so I should have NO problems with bass localization.. Any comments on this? If you see a problem.. then perhaps I could modify the parts express amp so that the high pass filter becomes 80hz. Is it simply a matter of swapping some a few parts like adjusting the bass boost? Oh, and if anyone can come across a Hercules Game theater XP driver that allows the adjustable crossover point let me know as I'll download it in a second. As of now I updated to the most recent version on the official site which now includes 7.1 processing... Yet it still has a crossover fixed at 540hz!! BTW, for clarification.. Do I adjust the LOW pass crossover on my plate amp to 125hz to match the high pass 125hz crossover point?