MOBS
The Mad Scientist
In short, setting your hpf cutoff lower allows lower frequencies to be sent to your speakers.......setting your lpf cutoff higher allows higher frequencies to be sent to your subs. For normal listening, I'd start with lpf on subs no higher than 50-60hz, and hpf on speakers no lower than 80-90hz.....it will still bleed lower hz thru on the hpf and vice versa for lpf, but the farther the hz is from the cutoff, the less amplification the hz receives. It's not just a hard cutoff, I guess you could call it a fading cutoff.