2002 Taco System Question

I've just gotten a whole system for Xmas and needed some help. I have replaced all 4 speakers with 6x8 Pioneer TS-A6872 r's and the 2 tweeters with Infinity 107t's, all 4 ohm. Headend is an Alpine CDA-9884 and Amp is an Alpine MRP-F250 and a Kenwood Powered Enclosed Sub KSC-SW10. The amp and sub will mount under the seat. Should I power the sub from the pre-outs of the headend or the Pre-outs of the Amp? Any suggestions on 2-ohm vs 4-ohm wiring would be great also. If needed, I can give specs on each device. Thanks

 

I would power the sub from the headunit preouts so that you can have control of it's volume separately. I'm not quite sure I am understanding your question about 4 ohm vs 2ohm(?) but in any case if all of the speakers are 4 ohm and each is on it's own channel the amp will "see" 4 ohms on each channel.