Let me get this straight regarding the crossover on my AVA 250 sub amp... Using high level inputs: when the crossover is set to 80hz, this means 80 hz and under is sent to the sub, and over 80 is sent through to the mains? with rolloff each way? Defeat switch set to "low pass" not "full" right?? I think this is how it is supposed to work, but it doesn't seem to have much effect on my main speaker response. It definitely effects the subwoofer, but doesnt't seem to alter the main speakers at all!