How to install a killer stereo for $500 (loads of pics) by StereoInstaller1

By diyauto
( 2 )

19 minute read

How to install a killer stereo for $500 (loads of pics)

Compliments of StereoInstaller1 @


Guys, the point of this little tutorial is to show you how to properly install a stereo in your E30 for a little over $500 total. The expectation is not just some lame-ass background tunes, but a solid, deep, clean, clear KICK ASS stereo, something you will enjoy listening to for years. Thhis is not just big stupid boom either, but nice crisp highs with excellent detail and a proper musical balance. This is a system that will play all types of music from Classical to metal, country, jazz, hip-hop...anything you throw at it will be crisp, clean and powerful.

This tutorial assumes you have a car that came factory equipped with Premium Sound, and that all the speakers are working and in decent condition. Hopefully, this also means that your entire stock system in intact, but that is really not an issue, it only means you can test your speakers easily. All we really care about is that the stock premium sound speakers are in fact properly working. We will be using he stock speaker wires from the amp to the speakers so that must be intact and complete.

Before we get started, lets make something else clear: you MUST remove your the dreaded "trunk tar" from your car if it is so equipped to fit this subwoofer. Lets just leave it to say I have my reasons for requiring this step, but it is essential.

You will need a quality set of crimpers, a cordless screwdriver, drill bits, assorted metric sockets, wrenches, pliers, wire ties, a handful of crimp connectors...look this over and make your own mind up if you feel this is something you can tackle. 

Most anyone with minimal experience can do this install in just a few hours, this isn't rocket surgery.

First thing (after clearing space and gathering tools and supplies) to do here is start with the equipment all laid out. In this case we have:

Jensen Power 5500 5 channel amp (currently $120 shipped on Amazon)

Pioneer DEH44 AM/FM/CD/USB/AUX indash receiver (currently $115 at WalMart)

Infinity Reference 1062W 10" DVC woofer (currently $60 shipped on Amazon)

4GA amp kit with AGU style fuseholder 

2 Pair of 15' RCA cables

And of course, a 10" E3010FU Fully Upholstered Subwoofer Enclosure from German Audio Specialties, also known as the LukeBox. Enough has been written by myself and others about this box. It is nearly magical in what it does, but you can search for that info at your leisure.

Like this:

So now, lets prep the box.

You will need to drill a hole for the woofer wire. Lots of my customers ask why I don't use a terminal cup. The short and sweet of it is they suck. They are weak and chintzy, the connector terminals actually melt (yes, as in 300 watts can MELT these crappy cups) so I require you to drill a hole. If you choose to install a terminal cup, have at it, but be warned, all of them are junk.

Anyway, get yourself something to drill with, a logically sized drill bit, a wire tie and some form of sealant. Anything from chewing gum to 100% silicone sealant is fine. Pull off a few feet of wire, drill a hole, shove the wire through it, put the wire tie on, put a wad of whatever sealant you have and pull it snug. No big mystery here, right?

Next, wire in the woofer. In this case, we are looking to give the amp a 2 ohm load on the subwoofer channel. This will get the most power out of this amp that it can safely develop. How we are achieving this is by wiring 2 4 ohm voice coils in parallel. What this means is connect the positive and negative wires to the first coil, then duplicate is on the other coil. If this is hard for you to follow, now is the time to stop and call a car stereo shop top schedule an appointment.

Use your crimpers to connect the wire. Make sure the terminal fits tightly, as this is critical to all electrical connections:

Now loop the wire over to the other terminal and connect it:

(need pic here)

Now, screw the woofer in place. I recommend using normal 1 1/4" drywall screws:

Torque it down firmly, but don't bend or damage the frame. It should be torqued down like anything mechanical, use a normal torque patttern. The seal is crucial, just take your time and get it perfect, it only takes 2 minutes if you have any clue what you are doing.

Now it is time to start on the cars wiring. First, get the stock amp out. It is in front of the antenna, under the . It will have 4 screws mounting it to the side wall. You might as well remove it completely and reattach the brackets and the check panel diode pack. Now would be a good time to clean those connections too.

Anyway, unplug your amp and untangle the wire all the way to the firewall, like this: 

Now is a fairly important part. You will be extending most of these wires about 3 feet.

You will need roughly 12 feet of 16ga speaker wire, roughly 3 feet of 16 to 18 ga blue wire and (optionally) about 4 feet of 16 to 18 ga red and black wire.

Cut the speaker wire into 4 3' lengths (remember, this is all approximate, but don't be stupid. Longer is easy to fix, too short is a pain in your ass, not mine) and strip back a couple inches of the stock amp harness wrap. You will need to cut ONE PAIR of speaker wires from the plug and attach one of the 3 foot chunks of wire using butt connectors, like this:

You will want to make sure you have proper polarity or it will sound like ass. Again, get it right here or call a shop! Do the wires one pair at a time until you have made 8 connections (4 pairs total) 

Here are your color codes (applies to every single E30 Premium Sound car I have ever done) 

RF+ Grey/White

RF- Grey/Brown

LF+ Grey/Red

LF- Grey/Violet

RR+ Black/White

RR- Black/Brown

LR+ Black/Red

LR- Black/Violet

Now that you have those 8 wires done, connect that 3' chunk of blue wire to the white wire, the red to the red/black (might just be red) and the black to the thicker brown wire.

Now, wrap that whole bundle of connections in tape. I am an absolute tape bitch, I use 3M "Super 33" only. Yeah, it is expensive but get it anyway, it kicks ass...don't be a cheap bitch:

Now what I do is wrap a strip of tape around the bundle every 8" or so to keep it tidy.

Leave that panel off, we are not done over there yet.

Now, it is time to do battery connections. What I like to do is make a nice neat mount for the fuseholder above the battery. I only do it because it looks cool, it has no functional advantage:

You can use a razor knife to make an "X" where you want the wire to come through and shove the wire through it. You need to allow for the bend of the wire, so call it an inch beyond the ends of the fuseholder. Check carefully to make certain there is no metal behind it, as that panel need to fit nicely when you are done.

Run the wire from the fuseholder to the battery, leaving about 10" or so top work with, the run the rest of it (you should have about 15' total) with the stock battery run, towards the front of the car, under the panel.

Next, measure 10" back from the firewall and cut another X right above the stock battery wire, like so:


and poke your power wire through, like this:

Next is the ground. Let me explain something here: paint does not conduct electricity. You need to connect to solid metal and you need to scrape it clean. I like to use the floor of the trunk, just immediately inboard of the main power cable.

(more missing pictures, WTF!)

I prefer to use a nice #10 screw, but 1/2" length. You can use a nut and bolt, whatever, but do NOT use something stupid, like a shock mount bolt, make your own ground point.

Shove it through the hole you made to put the power wire through, use a couple of zip ties to get it in place properly and reattach that panel, we should be done here for now.

Now, it is time to run RCA cables (and the sub level controller). I strongly recommend you run them through the grommet on the left side of the car, just like the factory does. This is the grommet hole here:

Take it out by removing the back seat and folding back the felt that covers the back firewall. You will see it at the top of the firewall. Pull the grommet, but don't remove it completely, as it will need to go back in

Now is a good time to remove your ski pass hole too. Whack it with a hammer, it comes out pretty easily:

Back to the RCA cables! So, now you have the grommet out. Take a good look at it, you can see where you can cut the rubber out and run more wires through properly, like the factory does...well, do it. Cut out the largest "blank" out. Shove through all 3 pairs of RCAs and the sub level controller cable. Don't worry about getting the lengths perfect just yet, but leave about 3 feet or so in the trunk.

Go ahead and put the trunk liner panel back on, but when you do, drape the RCAs, the sub cable and the speaker wires out of the top of the panel, like this:

Now carefully reinstall that grommet. Get it in place properly, it keeps your wires from getting damaged.

Now you can shove your sub box in place HOORAY! Shove that thing all the way against the firewall, but don't screw it down just yet.

What I like to do is cut out the little area at the bottom of the skipass hole I use tin snips to do this, takes about 15 seconds:

Looks like this when done:

Now, use 4 drywall screws to attach the box to the firewall. Nothing special is needed, but it is way easier to get the screws in if you have someone shove from the back. Just use 4 1 1/4" drywall screws, 1 in each corner around the skipass hole. It will suck the box against the wall, making the seal perfect.

Now that the box is in place, lets work on getting the wires to the correct length. What you want to do here is grab your amp and lay it in the trunk. Pull your RCAs so that the amp can be on the floor of the trunk with the RCAs plugged in, and have about 8" of slack.

You will be adjusting the amp before you mount it, so you will want to be able to get to all of the controls easily. You should have enough RCA to move stuff around as needed, but you need as much length as you can up front...the radio it connects to is up there, right? Well, proper routing means there are many twists and turns, so you need plenty of extra cable to do this correctly.

As soon as you have the trunk length about perfect, do the same bundling you did on the speaker wires. A quick wrap of tape every few inches. Too much and it is too stiff, too little and you have sloppy wiring. I prefer electrical tape to wire ties for this part, but do as you will.

Now for the part I did not get any pictures of at all...the RCA routing.

(pics to come later, unless I forget again)

First step is the 2nd biggest pain in the butt of the whole job: getting the door sill off. I use a large slotted screwdriver shoved under the front edge of the sill strip, then I twist it to pop that first retainer off. Yes, it is a raging pain in the ass and you can expect to break every single tab. If you get lucky, maybe you will only break a few...and by the time you have done 2 or 3 of these stupid things, maybe break only a couple...but even though I have pulled literally 500 or more of these stupid strips on these cars, I still break one every now and then. Back when they were new, I never broke them but the plastic is more brittle now. Oh yeah, pull the left kick panel too, but don't remove the speaker.

Back to the wire routing!

What the goal is would be to follow the factory routing. You can actually un-do the stock wire clamps and add your RCA harness in, but most of the time they break when trying to undo them. I generally just use a couple of wire ties to hold the cables in place...not too tight, either, as that can break wires over time (which is why I prefer electrical tape and also why I use kick ass Super 33 tape).

To deal with the seat transition, pull the front bolt of the seatbelt slider. It is pretty easy and then you can lift the slider enough to get the wire in place easily...just 1 (19mm? 18mm?) bolt and that goes pretty easy. Basically, tuck the wire from back to front, all along the floor of the car, just like the factory does. If you are willing to spend the time to take apart the factory wire retainers (they slide off to the side) and put your cables in the stock route, my hat is off to you...good job. The rest of us will just tuck them into the bottom of the carpet along the door sill.

Now run the RCAs up the stock harness (in front of the speaker) and toss a couple of wire ties on to keep it following the stock routing, Be tidy too, as the panel needs to get back on there, right? Now the crappy part is getting them to your radio. Since you have already pulled the underdash panel, pull the deck. Once the deck is out and the panel off, you can likely see where to go...but here is a critical part (one I wish I had pics of): make sure your heater controls can still move properly!

Run the wires over the steering column, then above the tubular dash brace on the left side of the radio, then let them drop out of the front of the radio hole. The wires should hang out roughly 8" from the dash after all is said and done.

OK, enough for now, I am back to work.

First, connect the front and rear together behind the deck. Just simple parallel connections, bypassing the deck wiring.

Second, you cut and splice extensions into the rear speaker wires going to the rear speakers, then extend the wires going to the front of the car, so all 4 pairs of speaker wires go to the trunk.

Oh, run a remote wire with the RCAs too..that is why that whole topic is going to be a separate thread.

Don't know if this pic helps or not

This will be even less help


Here is a quickie:

How to wire in the speakers on a non-premium car.

This covers late model non amplifed only at this point, but will be updated to cover early models soon.

OK, so pull your back seat and get the seatbelt out of the way, and find the rear speaker wires:

Now, grab about 20 feet of basic 16ga speaker wire, cut into 4 5' lengths. Wrap some tape around all 4, and shove it through the stock grommet:

Now get these things together:

Cut the rear wires and strip every end you have there. That would be all 4 aftermarket speaker wires and the cut ends of the stock wires:

Now, twist the pairs together. Remember that the black wires are positives on the stock wiring. I used the blue stripe as positive, but whatever you have, get the positives adn negatives correct and start crimping them as shown:

Note the technique, so when you are done you will have anice tidy bundle you can tape up:

Now, after 10 minutes, you are half way there

On to the next step, the wiring behind the deck.

What we did back there, if it isn't obvious, is connect the rear wires to the trunk wires and connect the front half of the rear wire run to the trunk how does that get to the front speakers? Simple, you connect them together behind the deck:

Note the colors: left rear positive now connects to left front positive and so on.

Now, as you see, the wires running from the trunk connect to the wires that run to the front and connect to the front wires behind the deck, so you need not run any wire at all, except RCAs and remote.

I am hoping that it is obvious that you don't connect these wires to anything else. They are just front speaker wires now, from the amp to the stock locations.