Here's a more general question. What crossovers do you recommend for my system. I have my dual RCA's going to my 4-channel. That will go out to my 4 6.5's and the line-out will go to my 2 channel to drive my woofer. The 4-channel amp has filters (high-pass for the 4 speaker outs and low to the second amp). So where do I need crossovers. I have those tweeters powered by the deck itself, not the amp. Any help is appreciated!