Ive posted this in the radios and electrical forum, but i thought id do it here too cause i thought more people would have input on how to do it in a cherokee.
So i replaced all the speakers in my cherokee and now im planning on adding a 4 channel amp to give em a little more power. Ive never done anythign like this so im kinda clueless. I am using my stock head unit so am i correct in using a RCA line output converter? And whats the easiest way to connect the speakers to the amp without running all new wires to the speakers? Should i just extend the wires where they would plug into the head unit to the amp? Thanks for the help, Matt
I would definitely run new wiring for the speakers at least, that will save you a lot of trouble in the long run, especially because after you run the RCAs to the amp the wires for the speakers have to come off the amp, so the stock wiring isn't going to cover that (depending on where you mount the amp i guess), but like he said, more power so you need bigger wires to get the full effect, I would run 16 gauge from the local stereo shop, you can usually get it for $.20 a foot, and with my amp mounted under the rear seat 60 feet was more than enough to do everything I needed to all 4 speakers.
As far as the RCA converter goes it is pretty straight forward, you just tap into the speaker wires coming off of the stock unit and then run the RCAs to the amp.
Since you are using the stock head unit you aren't going to have a remote control, which is the wire that an aftermarket unit uses to tell the amp to turn on when the stereo turns on, with stock units the best thing you can do is tap a single wire into the switched power source (violet / orange stripe wire on my 88 XJ) and run it to the remote terminal on your amp, that way the amp isn't on full time, but turns on when you turn your Jeep on and is ready for when the stereo turns on.
First off, if you havent bought the amp yet, look for one with high level inputs.
http://www.crutchfield.com/S-9LSX8q2eq6R/cgi-bin/prodgroup.asp?g=120&avf=N&nvpair=AG%5FNumber%5Fof% 5FChannels|FF4%40Channel&nvpair=AG%5FGeneral%5FFea tures%7CYCSpeaker%5FLevel%5FInputs#see_all
that is a link to the crutchfield site. All the amps listed are 4 channel with speaker level inputs.
for the wiring, what I would do is pull the HU out of the dash, and pull all the stock speaker wires. At the speaker ends, unplug the wires, and tape on the new ones, that way when you pull, the new ones are already run. This will probably require some finness, and probably some time. Then, run the stock wires to the speaker level inputs on the amp, and viola, all ran. I would mount the amp under the driver or passenger seat, or under the back seat if you have enough wires. I hope this made sense, if not, ask.