i have an alpine head unti -> CDM-7859RB, with 1 pre-amp output with subwoofer level control. i want to install an amp and sub, the amp will only run the sub, so what will i need,? and how do i do it?

You need: thick wire for the amp (preferably red ), a smaller piece for the ground (preferably black). A pair of RCA leads (with the male ends at each end). A thinner (usually blue) 'remote' wire and thats basically it! Just run the red wire from the +(ve) end of your battery (use some lugs to be neat and tidy!) to your boot (put it through a hole in the firewall and then under the carpet and under the back seat). Find your 'remote' wire from the headunit at this stage and run that in the same place... do the same with your RCA leads (some people like to run them seperatly, but i've never had any problems with having them all in one bunch of wires). Then find a bolt or screw in the boot (one thats screwed into the chassis) and put your black wire under that and tighten it back up. Hook it all up to your amp (careful not to let any wires touch - or disconnect the battery) - then hook up the sub to the speaker outputs and ya done! probably have to tune it a little to get it right, also make sure you have your low-pass filter turned to "on". Some original photos have not been recovered yet.

cool. thanks mate

ummm id like to say a few things about this your earth should always be the same guage as your power wire as thats the trip wire sorta thinggy and if your power is greater than your earth not good. also u should always run your remote and rcas away from power can cause distortion wot i did i ran the power right down the drivers side and ran the remote and rcas down the centre as the centre console covered up any bumps ALWAYS RUN YOUR POWER AWAY FROM SPEAKER REMOTE AND RCAS!!!!!!!!!!!!!!

theres a shorter run of wire for the earth - thats why it doesn't need to be as higher gauge And yeah if you can be bothered doing the whole seperate leads thing go for it, personally i've never had any problems since I have the stinger sheilded RCA leads. Some original photos have not been recovered yet.

You should also have a fuse holder within 6 to 12" of where you get power from (i.e. the battery) You'll need a fuse in it obviously. The gauge of the earth wire should really be the same, but profided you keep it under 2 foot you should get away with a lower gauge.

Quote: Originally Posted by platinum theres a shorter run of wire for the earth - thats why it doesn't need to be as higher gauge And yeah if you can be bothered doing the whole seperate leads thing go for it, personally i've never had any problems since I have the stinger sheilded RCA leads. Hmmmm, im glad you dont work for a car audio installation joint :P Your earth has to be the same gauge as your power simply because it has to take the same ammount of current as the power lead, no matter how short it is. (usually shorter earth lead the better). It is ALWAYS best to run your RCA's and speaker cables on the opposite sides of the car whether its shielded rca or not, i saw stated earlier that run your remote with your RCA's, NO, remember its a power wire to.......my88vl is right, have a nice fuse (usually about 30A rating) nice and close to the battery, so if you get a short it aint gunna burn ya car to the ground. You said your headunit only has 1 rca output, depending on your amp you might need a splitter, so as your run signal into all the inputs on your amp. Bridge the channels on your amp to run your woofer (all depending on what amp and woofer it is). Make sure your power cable isnt running over any sharp bits on the body of your car and you'll be safe also. Email/PM me if you need a hand with anything. Chris Some original photos have not been recovered yet.

heh - well i've installed enough to know anyway... but I could be wrong.. This is what I've thought, the whole reason you have massive thick cable is because you loose power the longer the wire runs, so if you're only running a short cable, it doesn't have to be as thick. (of course it has to be able to match the amps power rating, but you don't need 0 guage wire for it!). Oh yeah I forgot about the fuse ops: sorry bout that Some original photos have not been recovered yet.

Nah dude, the reason for thick wiring is to reduce current resistance. Larger amps draw more current from your battery and need larger cable to run through. Think of it as water through a pipe... more water needs lager pipe.

This man knows his stuff. I will never pay shoddy car audio installers again. They ran ****ty Aerpro wiring through to the amp, that should really have been used as a remote wire it was so thin. Basically, when you run a cable the length of the car it is going to lose some power along the way, the thinner the cable, the bigger loss. Its like Burgs said, if you run a 200m garden hose, don't expect there to be water comin out the end.

ah right yeah thanks BurgundyCalais, what I wanted to know is if you say only have to run your 'gardenhose' 20m it should be right... heh - or do you guys all run your earth wire to the front of the car? or am I missing the point here as usual Some original photos have not been recovered yet.

As long as your power cable is the same guage as your earth wire, and you run your RCA's seperately to the powercable along the side of your car, then you'll be sweet! Some original photos have not been recovered yet.

thanks guys for all your input. i am a little confused... it sounds like your saying every wire needs to be seperate from the others. there are 3 wires that will need to reach the boot (rca's, remote, and power) yes? but i only have 2 sides of my car also, is it a bad idea to mount the amp to the sub box? the amp and sub are both alpine ****, i think is an r10 sub, not sure on amp model. also, where can i get all this stuff from... like fuse and case? any1 know of a nice location for earth? thanks again

you will have 3 power wires actually - -(ve) earth, +(ve) power and the remote wire turns your amp on and off when you turn your stereo on and off so you don't flatten your battery. As I mentioned before it's usually a blue wire coming off your headunit. You should technically put your RCA's on the other side of the car, incase you get interferance. I don't think it makes any difference really, but hey it's good practice. I don't think it's too bad of an idea to mount it to the box, but I guess with all the vibrations it may not be too good for the amp - but i've seen it done before plenty of times, and if you intend of moving it round it's the better than having to unscrew it all the time. Just remember to mount the amp according to which direction the fins run (should tell you in the instructions). Or you might get heating problems. Just go to your local car audio store and find a fuse and fuse holder - they'll have them there about the earth wire - well, I would just screw it into the chassis, there's a few points already in the boot, just find one. But I don't know what these other "experts" think about that Some original photos have not been recovered yet.

thanks platinum, so its ok to run remote and power wires together, just not either of them with rcas? with the power wire, do i attatch it directly to the clamp thingy that is already connected on the positive side of the battery?. then say 8 inches down have the fuse case? i took out my ash tray and scooped out some wires behind the unit, do i basically locate the associated green wire and conect some wire with electrical tape for the remote hook up, cause it looks like thats what the audio place that installed it did with the speaker wires.

yeah you can run all the power wires together (thats essentially what the remote wire is) Yeah just attach it to the battery itself, when you're buying your fuse holder try and buy a proper lug for it and then you just bolt it on. And yep, a fuse holder within 25cm of the battery. Yep, find the right wire, and solder your extra remote wire to it, then tape it up, again you can also get a plug for this if your headunit wire has a socket already attached to the end of it Some original photos have not been recovered yet.

wicked, thanks mate.. i'll let u know how it goes (probably early in new year)

Run your RCA's down the middle of the car on the outside of the transmission tunnel. Run your power wires down one side of your car and speaker wires down the other. Use same guage power cable and ground cable for your amp; no less than 8 guage. Use a fuse holder with appropriate fuse (check amp specs) about 20-30cm away from your battery. Keep your ground cable less than a metre long. Turn high pass filters on for speaker with cones 6" or less, no filter for 6"x9"'s and low pass for subs. Turn your gains right down, then turn your head unit volume to about three quarters volume. Then slowly up your speaker gains until you can hear them strain, then back off some. Then slowly turn your sub gain up until it matches your speaker volumes. With all this done, you'll be sweet as ya nana!

I use 4/0 gauge wire straight from my battery to amp and run a 40 gauge wire as the ground :roll: i love watching the ground cable dicintergrate and set fire to my carpet ops: all jokes aside, what BurgundyCalais said is pretty much right. Id say you should only need to use 8 gauge wire from battery to amp (and for ground off amp). But for future modifications always best to run 4 gauge into a distribution box in the boot, splitting it to 8 gauge wire going to your amp (and allowing for future amps). Cheers Some original photos have not been recovered yet.

Yeah, by the way, you don't NEED to do all the stuff I said, but if you don't you'll run the risk of not getting the most out of your stereo equipment. And to me, wasting amplifier potential, just to save a few bucks on wiring seems pretty stupid. Cheers and good luck dude! Some original photos have not been recovered yet.