Hi all, I just hooked up a Boston Acoustics PV400 subwoofer (I know, I need to upgrade) via RCA cable, and don't understand how to set the crossover frequency. Crossover is meaningless for DD or DTS because the LFE channel is discrete, right? However, for Pro-Logic the "LFE" is simply derived from the matrixed stereo signal....? Does the AV amp handle the crossover duties (I do get some bass when using PL, so I know that the AV amp is sending something)? If so, I cannot find any way to adjust said frequency. What am I missing? Thanx!