Ok.. so last year i bought a system, onkyo sr-605 reciever, polk audio cs2 center, polk audio m20 fronts, and hsu research vtf-1 sub. Im not really sure what i should set the sub up to with the crossover, frequency and all that other jazz, i know nothing about audio systems, no clue what any of it means. Not sure what i should set the Hz at of each speaker, the default on my receiver is like 100 for everything. Is closer to 0 better for hz? What does doublebass mean?