I need some help on hooking up a 4 channel amp in my buddies car. I need to hook the amp up to a pair of subwoofers and a set of speakers. His deck only has 1 set of pre-outs. The amp can use line-level or speaker-level inputs, so how do I wire it all up?

 

you should use line but this setup isn't the best since usually you would use the hp filter for normal speakers and lp for subs so you'll either have highs coming out of your subs or bass coming out of your highs

 

use a set of splitters right off of the back of the HU, then on the amp you should be able to hook the subs to channel 1 & 2, and the speakers on channels 3 & 4, all 4 channel amps that ive delt with allow you to set channels 1 & 2 to run LP or HP or FULL, and then set 3 & 4 to LP HP or FULL.

hope this isnt confusing, what im trying to say is that most amps will let you set seperate setting for the 1/2 channel and 3/4 thus allowing you to run a whole system off of one amp

 

If it's a 4 channel amp (meaning two separate 2 channel amps in one unit) first, you need to hook up a 2 or 3 way electronic crossover to your head units pre-amp outs and then from the crossovers outputs you can hook up into the separate inputs of your subwoofer amp and the high frequency amp.

 

Ok, I got 2 sets of splitters today and I was talking to the guy and he said to hook them in at the amp instead of at the head unit. Does it make any difference? The amp has a Hp and Lp for each set of channels, so I shouldn't need a crossover, right?