alright on my amp there are 2 dials that say HPF and LPF, i can turn the dials to adjust, then there is a switch that says HPF, LPF, and FULL, above the swich it says FREQ.,i keep it on full cus thats how it was when i got out of of the box, but i was messin with it and found that it makes the bass louder and deeper on HPF( i think) waht does this stuff mean and is it bad to keep it on full? or is it bad to keep it on HPF or what?