Installing a Subwoofer guide

I've recently installed my Subwoofer. So I thought I'd show you how I've done mine if anyone is completely lost.

Make sure you have an Aftermarket Headunit with these outputs on the back.
-SW-Line out
-Remote line (recommended but not essential)

As well as the following items.
An Amb
A Subwoofer
A Sub Box
A Wiring Kit

Just so you know what I mean I've added links to a cheap punchy 500RMS build but obviously choose whatever you like as a set up within your own budget and personnel taste.


20130102210217.jpg


I've ran my power cable through a grommet under the glove box.

If you remove the glove box you a see it clearly but its not an easy job to get a wire through. I lifted the loom to the side using a screwdriver and pushed the Power cable through.

20130104221528.jpg


If I was to do it again I would say its best to make a new hole in the grommet then pull the Cable through that then lift the loom to the side with a screwdriver and pull the cable through. This way the grommet will sit flat and also prevent leaks but because of my "that will do attitude" I couldn't be arsed so I just covered in a sealer. :thumbup: (plus no one will ever see it behind the glovebox)

20130105132306.jpg


I had to remove my airbox and battery to reach the power cable sticking out the grommet once it was through to the engine bay, then I could pull it as far as I needed to reach the battery. I then sealed the Power cable in place on the grommet.

Before you put the Glovebox back you will need to remove (or install) the Headunit and plug in the Phono leads into the SW line out slots, and also connect the Remote Line (if you have one).

20130102210233.jpg


Theres a gap above the headunit from the back you can feed the wires down into DIM slot. You can also use this gap to hold up any wire as you re-install the headunit to prevent them from get stuck behind it and your head unit not sitting flat.

20130105132403.jpg


I tucked all my audio leads behind the passanger side trim that runs along the floor of the door and into the rear doorcards then under the rear seats and into the boot. You wont need to remove any trim to do this.

20130104214343.jpg


I also hid alot of the excess wiring behind the rear doorcards if you looking to keep things tidy. Then I pulled the leads under the boot carpet to rear of the car and into the Amp (power cable, Phono leads, Remote line).

20130104214639.jpg


If you remove the wall carpet trim near the rear lights you will find theres an earth there so you can just unscrew the bolt and attach your line to the existing one and into your Amp. Attached your speaker cable to your speaker and then into the Amp and your done!

20130104214717.jpg


My amp also came with this little Bass booster thing so I attached it on the dash. Looks rubbish but you get the idea of what you can do if you experiment.

20130104221458.jpg
 
Last edited:
Nice guide but did you protect the power cable were, i assume it's under the gromit?

It'll be a lot safer going through the gromit, if it rubs through on the metal (over time) it will short out and could cause a fire.
 
Nice guide but did you protect the power cable were, i assume it's under the gromit?

It'll be a lot safer going through the gromit, if it rubs through on the metal (over time) it will short out and could cause a fire.

Good point, can almost guarantee that will wear through until the live hits the chassis at which point the fuse will hopefully blow (Make sure you have the correctly rated fuse in the live cable to match your amp)
 
Nice guide mate, did you run your power lead down the same side as the audio cables?

Yes thats right. I've added a couple of extra pics to make it clearer. Power Cable (red), Remote line (blue), Phone Cables (silver)

Nice guide but did you protect the power cable were, i assume it's under the gromit?

It'll be a lot safer going through the gromit, if it rubs through on the metal (over time) it will short out and could cause a fire.

Good point, can almost guarantee that will wear through until the live hits the chassis at which point the fuse will hopefully blow (Make sure you have the correctly rated fuse in the live cable to match your amp)

Theres not much chance of a 4AWG rubbing on plastic trim then breaking and causing a fire but if your worried use a little cable trim or wire tape to stengthen it. I've sealed mine from both sides so theres no movement at all.

I've put my fuse behind the wall carpet trim in the boot so its hidden away.
 
Theres not much chance of a 4AWG rubbing on plastic trim then breaking and causing a fire but if your worried use a little cable trim or wire tape to stengthen it. I've sealed mine from both sides so theres no movement at all.

I've put my fuse behind the wall carpet trim in the boot so its hidden away.

It doesn't take much at all to wear the cable through, I've had personal experience of this on 4AWG hence my comment. And when I had a damaged cable that was cable tied away from sharp edges. It must have been the vibration from going over bumps knocking the cable onto the panel edge.

Just something to be aware of and worth noting that punching a hole through the grommet and passing the cable through would be a better way of doing it
 
I've put my fuse behind the wall carpet trim in the boot so its hidden away.[/QUOTE]

The fuse is in the boot ? It should be as close to the battery as possible ?
 
I dont really understand what you mean to be honest.

Punching a hole though the grommet will just take you to the same way I went through anyway but means the grommet sits flat, which cosmeticly is better and I don't disagree with that hence I already made a note in my original post.

The other way is through the centre of the loom which requires no holes, need but you would need to remove the loom or retie the power cable into the loom which is a hell of a lot of work and even if you did this I'm not sure a 4AWG will fit and theres not a lot of space for it.
 
From the photo it looks like you have the cable going between the grommet and the metal panel, so it's free to rub against the metal panel edge? Perhaps I'm not seeing things correctly?

Normally people punch a new hole through the grommet and feed the cable through the fresh hole, keeping it away from the bulkhead and loom.

Fuse should really be near the battery, just means it blows fractionly quicker in event of an issue. Realistically, not sure it really makes much difference.
 
Just a thought - aren't you meant to run the power leads down the other side to the audio cables because it can affect the sound. Or am I making this up? ;/
 
Real Audiophiles "say" it can cause light distortion, but honestly unless they are tightly tied or in a loom it doesn’t do anything. If your worried just make sure you using the highest grade of cable you can afford. i.e 0AWG and decent SPL phonos. The remote wont matter.
 
Just a thought - aren't you meant to run the power leads down the other side to the audio cables because it can affect the sound. Or am I making this up? ;/

I was told this too when i used to fit audio equipment but this was about 18 years ago when things were starting to get big, modern stuff could be better now.

The power cable is easy to sort, cut a slot and an hole in the gromit to take the cable away from the body, a bit of sealant on it now to help were you slit it.
 
I was told this too when i used to fit audio equipment but this was about 18 years ago when things were starting to get big, modern stuff could be better now.

The power cable is easy to sort, cut a slot and an hole in the gromit to take the cable away from the body, a bit of sealant on it now to help were you slit it.

Mostly DC so probably not as much of an issue as if it were mains or AC, unsure how 'smooth' a cars electrical current is though so it might still induce some noise to unshielded wires close by.



/edit

quick google looks like 300mv ripple spiking anywhere upto +-1V is fairly normal in a car
 
Last edited:
Phonos running alongside power is fine as long as the phono cable is shielded and that shield is 100% intact. You'll only really get alternator whine caused by running the cables together if you use a really cheap cable or the cable is damaged