setting filters

I have no clue how to set my filters. I really don't have that good of a keen ear to notice much difference. I have an alpine head unit. You can set the bass filters at 80, 100, or 200 the treble filters are 10, 12.5, 15. I have pioneer 4x6 in the dash. Then stock in the door and rear side panels. I also have 2-12" RF Punch z's that are pushed by 1200 watt xplod amp. Those speakers can only handle 200 MAX so I don't want to go blowin the sh*t up. I had them set once but the battery got disconnected and I forget how I had them set. I'm looking to keep the high pitches in the speakers (no bass) and leave the bass to the subs...obviously. I'd also like to see if I can get anymore bass out of those subs. Maybe a change in the box. Right now its just a cheap best buy special. If I make my own box will I see dramatic change? Or with subs that low in power is it just best to get a new system? I drive a 1995 GMC Jimmy 2-dr also.1995 GMC Jimmy 4.3 Vortec

What is the modle of your alpine deck? It sounds like you are describing the bass engine function instead of a high or low pass filter.