The crossover point is the point where high/low frequencies are separated, correct? So if you set the sub crossover to 150 Hz, anything higher than that would be omitted from going to the sub.

So wouldn't you want the crossover point on the fronts to be set at 150 Hz as well? This would block anything below 150 Hz? Or would that block above 150 Hz? I guess I'm a little confused about how crossovers actually work. There must be something I'm missing, or they wouldn't have put three crossovers on the amp. I guess so you can set a different level for each pair of speakers...but do crossovers block out higher frequencies, or lower frequencies?

I just assumed for the sub channel it would block the higher frequencies, and for the fronts and rears it would block the low frequencies.

Another thing, my sub is in a ported box, so the Subsonic filter at OFF is the correct position. But if the crossover only goes down to 30 Hz, then there shouldn't be anything going to the sub lower than that. So why the need for the filter? They say that the subsonic filter removes frequencies not audible to the human ear. These frequencies are only robbing power from the amp. So I guess the new question is, how do the subsonic filter and crossover relate?