BMW E30 Rear Speaker Installation
Jared Fenton

Difficulty Level: 3
Difficulty scale: Adding air to your tires is level one
Rebuilding a BMW Motor is level ten

     Next in my series of tech articles on upgrading the E30 sound system is the rear speaker installation for the E30. In my previous article, I detailed the steps involved with installing the front speakers. In this article we will focus on installing the rear speakers.

     As I said before, the stock “premium” sound system on the E30 BMW 3 Series is a good system for the average Joe, however if you are a total music freak like me, the stock 5-¼ rear speakers just don’t cut it. I had a set of really nice JBL 6x9 3 way speakers left over from my dearly departed E21 320is. I really wanted to use these in my 325is, however they won’t fit in the stock locations. The stock speakers in my E30 were in two enclosures on the rear deck that also held a tweeter angled at 45 degrees. The whole enclosure screws onto the rear deck. The first step is to remove these enclosures. They are held in place with screws around the perimeter of the enclosure. Very carefully pry off the speaker grilles and remove the screws. Now lift off the enclosures and disconnect the leads to the speakers. 

     Now with the enclosures removed, there is a hole and recess built into the rear deck. I tried for a while to figure out some way of getting the 6x9’s in the holes, however they won’t fit. I briefly considered even cutting out the sheet metal to gain clearance, but I really don’t want to cut any metal on the car. I eventually went down to the local best buy and found some really nice universal fit speaker spacers. These sit over the factory holes and have enough height to allow the 6x9’s to fit in with no clearance problems. I had originally considered painting the spacers tan, to match the interior of the car, however the black finish looks very nice and seems to “fit” in with the esthetics of the car.

     Before we start to install the new spacers, we will need to run new wiring for the speakers. The factory BMW wiring uses a common ground system of wiring for the speakers. There are ways of adapting the current wiring to make it work; however I found it easier to simply run new wires. I started by measuring off enough wire to run under the backseat, down under the doorsill plates, up through the dash and up into the head unit. Do this for both sides of the car. It’s important to remember to use a single piece of wire with no splices when hooking up speaker wires. Every time you cut or splice the wires, you cut the signal from the head unit or amplifier in half.

     Now run the speaker wires on either side under the rear deck and into the factory holes for the old enclosures. Next, place the new spacers over the factory holes, and screw them down onto the rear deck. Now pull the wires up through the spacers and connect them to the speakers. Now stuff the wire down into the enclosure and install the speaker into the spacer, as you would mount any speaker. This varies from model to model of speaker, however it is essentially the same idea for every speaker. Now place the grille over the speaker and push it into place. Repeat for the other speaker as well.

     Well, there you have it - it's really not too difficult at all.  If you would like to see more technical articles like this one, please continue to support Pelican Parts with all your parts needs.  If you like what you see here, then please visit our online BMW catalog and help support the collection and creating of new and informative technical articles like this one.  Your continued support directly affects the expansion and existence of this site and technical articles like this one.  As always, if you have any questions or comments about this helpful article, please drop us a line.