sorry, corrected links here...LONG! - The Z3 (E36/7) Message Board

My car stereo story…

My main objective was to make the stereo sound good at freeway speeds with the top down and have absolutely no visual evidence of aftermarket equipment. I’m not one of the “ears bleeding” types of guys (I’m a musician, I don’t think bleeding ears would help my career!) and I prefer the stock look, plus it cuts down on someone attempting to steal your stereo if it looks stock.

I have a friend that works at Polk Audio as an engineer designing speakers. He was able to hook me up with a pair of their DX 3055 5.25” component fronts with a 1” tweeter and passive crossover, and DX4 4” coaxial rears. I was lucky, I got both pairs for a total of $58!! (older models go on sale when the new ones come out).

I set to work installing them, removing the door panels and replacing the 2” tweeter in the door with the 1” as seen on MZ3.net DC stereo install. The tweeters were a little tricky, I had to dremel the mounting bracket that came with the speakers, but it fit nice and tight against the grill. I left the factory 1” in place, but disconnected them.

The kick panels were a breeze, simply remove the kick panels and swap out the speakers. I had to solder on new connectors, but that was pretty simple.

I tried them out. The sound was much improved over stock, but I was missing mid-range frequencies because of the factory amp that sends high, mid, and low to three speakers…I’m only using two. The next step is to fix that.

CarlB recommended the Blaupunkt PA 2100 2-channel amp as the best that would fit in the factory space. Although he never used it himself, he heard good things about it. I decided to give it a shot. I found some pretty cheap ones on ebay, but after looking at shipping rates, I decided to order through www.crutchfield.com and buy a scratch and dent model (I’m removing the cover anyway, what do I care if it’s scratched?!).

It came the next day (with regular shipping! Way to go Crutchfield!) so I started ripping out trunk carpet that day. With the cover removed on this amp, it is really tiny, so I thought I might look for another location to put it, and use the factory amp to power the rears. It worked! The amp fits (barely) next to the black storage bin used to access the spare tire. I placed it on a thin board and up against the rear of the car sitting vertically (sorry I don’t have a picture). The wiring diagrams on mz3.net saved a lot of headache as well and were dead-on accurate.

Success so far, now to install the rears. Thanks to Mark Volk for sending me instructions for the Z3 factory upgrade which details step by step how to disassemble the interior of the car! Because I was using the factory amp to power the rears, I had to rewire the connectors into the 2-channel amp to send signal to the rears. I cut/spliced the factory input of the fronts with the rears so the rear signal was now being used. The amp modified the signal and sent it out three ways (high, mid, low). I then spliced the mid and low to use them for my rears. I experimented using the low, but the mid sounded much cleaner.

Now to wire the rears. I discovered while pushing cable through the grommet that there is already wiring for rear speakers in the 97 without rears factory installed! It’s under the carpet next to the driver’s chair with an amp clip attached to it. That saved some time and wire! Now to try everything out.

It sounded great with the car off, but I had a TON of engine noise with it running. I was running the new amp’s ground directly to the battery ground. After talking with the car installation guys at Best Buy, they said that wasn’t the best choice, so I found another ground bolt nearby. Some of the engine noise was gone, but not all. It turns out that the high-level input converter that comes with the Blaupunkt amp is its weak link. I replaced that with a Rockford Fosgate equivalent model, and some monster cable RCA wires and success! No more engine noise.

I put everything back and there is NO VISUAL EVIDENCE OF ANYTHING AFTERMARKET!!! (I did add rear speakers that were not there beforehand, but they were an option during that model year). You can’t see the amp or any of the wires. I’m very pleased.

Overall this project was WAY more involved than I planned. For my first amp installation, I learned a lot and I’m sure that if I ever do this again, it will be much easier, but for now, if I never see another soldering iron or speaker cable again, I will be happy!