setting hpf and subsonic filters

Normally you would use two sets or RCA cables, one from the Front pre-out of the HU and one from the Rear pre-out from the HU to supply a signal to the 4-channel amp.  If the HU has a separate Sub pre-out, a third set of RCAs is used for that.  If not, assuming the 4-channel amp has a pre-out, daisy chain the sub amp from there.  If you are sending a single full-range signal to your sub amp, there is no good way to daisy-chain a 4-channel amp from that - unless you don't care about front-rear fade?  Then use a y-cable.

I was thinking about seeing "Dark Knight" this weekend.  I hear it's pretty good.

Hey if somebody has a stiffening cap laying around and wants to stop their headlights from dimming, I have a plan that should work.  I do not want you to go and buy a cap but if you have one and want to try this, let me know how it works.  A (.)5 farad cap should be plenty.  If you use a 1 farad you may need 4 diodes to handle the charge current.  You will be charging the cap everytime you turn on the lights.  The diodes are necessary, they prevent the current from supplying the amplifier.  For testing purposes you could simply connect the diodes, the cap and a headlamp bulb to try it.  Let me know if it works.