bbain

Hello all,

First time poster here on the forum. I want to say thanks to everyone for all of the great info I have gleaned from you.

I recently installed a new stereo system in my 1992 968 coupe consisting of the following:

- Alpine iDA-X305 Head Unit
- Polk Audio db461 4"x6" rear speakers
- Polk Audio db5251 5-1/4" component speaker system in front door

Here's what I learned from my 968. This is in addition to the excellent information I viewed on this forum.

FACTORY 968 INSTALL
My car had the 6 speaker system installed. It included a mid-range 5-1/4" speaker (Nokia) under the arm rest in the front doors with a 1" tweeter (Nokia) in the upper front doors. It also had a 4"x6" rear speaker (Blaupunkt) under the rear window on each side.

The factory wires for the speakers in my car are as follows (wires connected to the speakers or factory colored wires run):
- Front left negative = brown/white
- Front left positive = white
- Front right negative = brown/black
- Front right positive = black
- Rear left negative = brown/yellow
- Rear left positive = yellow
- Rear right negative = brown/red
- Rear right positive = red
- Power from ignition = green
- 12 volt constant power (for head unit memory when car is off) = red
- Ground = brown (2 wires tied together)
- Power antenna = red/black

The factory door speakers (5-1/4") connect via a single quick-disconnect connector on the outside of the speaker mounting panel. This connector sends signal to the 5-1/4" speaker. Once you remove the speaker mounting panel that houses the 5-1/4" speaker, you can see that the speaker wires that connect to the 5-1/4" speaker have an in-line mid-pass filter.

The factory 1" tweeter speakers connect via 2 brown wires (not to be confused with the earlier stated ground) that run into the top of the door. I did not trace these wires as I did not need them and as such, I did not use them in my new install.

THE 4"x6" SPEAKER INSTALL
The Polk Audio db461 4"x6" speakers installed directly into the factory housing. Note that the factory 4"x6" speakers are actually 4"x6" m mounts. There is about 3.5 inches of mounting depth in this location so I also installed baffles. There is also a plate, that when removed, will allow a 6" speaker to be installed here (this has been noted in several other posts). I left the plate and opted for the 4"x6" speakers.

THE 5-1/4" POLK SPEAKER INSTALL
The Polk Audio db5251 5-1/4" component speaker system comes with a 5-1/4" mid, a 1" tweeter, and a crossover. The wiring was easier than the mounting of these speakers. For the wiring, I connected the corresponding side wires (positive/negative) to the Polk Audio crossover and then connected the 5-1/4" and 1" tweeters from the crossover per the Polk instructions. For the mounting, I had to mount the 5-1/4" speakers on the back-side of the speaker door panel as opposed to mounting them through the panel as the factory speakers are. The reason for this is because the Polk speaker baskets are larger in diameter than the factory. This also required me to enlarge the factory panel hole for the 5-1/4" magnet as well as cut a very small portion (1"x2") of the arm rest away on the mounting side (not visible). This resulted in the 5-1/4" speakers mounted behind the factory grill under the arm rest.

THE 1" POLK TWEETER INSTALL
The factory 1" tweeters are actually a one-piece unit that includes the factory mounting mechanism as well as the factory 1" tweeter speaker and grill. I ended up breaking the factory 1" tweeter from the grill and mounting mechanism and using the factory grill/mount to install the Polk 1" tweeters. This resulted in the Polk tweeters looking like the factory tweeters.

THE ALPINE iDA-X305 INSTALL
The Alpine iDA-X305 installed directly into the factory opening using the Alpine mounting plate. Here are the wire connections for the iDA-X305:
- Front left negative = white/black
- Front left positive = white
- Front right negative = grey/black
- Front right positive = grey
- Rear left negative = green/black
- Rear left positive = green
- Rear right negative = violet/black
- Rear right positive = violet
- Power from ignition = red
- 12 volt constant power (for head unit memory when car is off) = yellow
- Ground = black
- Power antenna = blue

FINAL RESULTS
I chose the Alpine iDA-X305 because in my opinion it controlled the Apple iPhone 3G better than any other unit I had researched. In my opinion it does do that and I am extremely happy with navigating through my massive song, podcast, custom playlist, and more. The Polk Audio db461 4"x6" rear speakers give a very good bass response, especially considering that the speakers are 4"x6". The Polk Audio db5251 5-1/4" component speaker system produce great highs from the tweeters and smooth mids from the 5-1/4" speakers. I may opt for a 10" subwoofer in a custom mount of one of the rear deck cubby holes, but I will wait and see how my current upgrade pans out. So far, I am really happy with the install.

Hope this helps.

Damian in NJ

Well written, and welcome aboard.

Chaos

Very nice,thank you. If and when I upgrade I will use your post as directions !

mikey_audiogeek

Great info, thanks for your efforts!

guywitha968

Hello bbain. New member here. I just pulled the head unit from my 968 today and was planning to install an new unit. I don't have the connections you mentioned. I have only a round miltipin DIN connector. I suspect this connects to an amp somewhere as the original has no speaker outputs. Did you have to route wires to an amp location somewhere to get to the speakers? If so, where is this amp? I know I can find it by following the wire, but that may be a difficult task that is not necessary if I know where it was. Can you help?

Thanks, gm

sydneyman

bbain, welcome and thanks! i wish i could say my first few posts were as informative!

bbain

Hi guywitha968,

The multipin DIN connector is the wiring harness. It allows you to quickly remove the stereo head from the car by disconnecting all of the wires in one connecting point. Most reputable vendors will have an adapter (if needed) that plugs into the new head unit and connects to the existing wiring harness. If you look at the color of the wires in your existing harness you will see the same colors I described in the Factory 968 Install section of my post.

In my case, the PO had removed the wiring harness and hard-wired the head unit into the system. I chose to put inline wire connectors on each wire when I installed my new system.

As far as an amp is concerned, I am using the 50W x 4 power from the Alpine iDA-X305 unit. With the 968 cabin being so small, for me it delivers plenty of power, clarity, and punch through the Polk speakers.

On a side note, the Polk Audio speakers have great bass response (imho). This is something they are known for and why I have Polks in my house as well. With this in mind, I will not be installing a subwoofer.

Hope that helps!

guywitha968

Hello bbain. One thing you didn't mention. Where is,or was the original amp located? Thanks!
gm

zerokreap

Great thread...thanks for taking the time to write it all out. This will be my first project on my 968.
Stereo installs can be a pain, but this will help. Thanks
zk

Jack.Harris

What do you do with consideration of a factory alarm? When the alarm is engaged the code has to be entered on the factory stereo head unit? When you replace that what do you do to deactivate the alarm? ODBII reset?
Nice article. Well documented. I am planing a Speaker upgrade and would like to do a new head unit too but am concerned about the factory alarm option.

4kix66

THANX!!!!

968joy

[QUOTE=bbain;7195899]Hello all,

First time poster here on the forum. I want to say thanks to everyone for all of the great info I have gleaned from you.

I recently installed a new stereo system in my 1992 968 coupe consisting of the following:

- Alpine iDA-X305 Head Unit
- Polk Audio db461 4"x6" rear speakers
- Polk Audio db5251 5-1/4" component speaker system in front door

Here's what I learned from my 968. This is in addition to the excellent information I viewed on this forum.

FACTORY 968 INSTALL
My car had the 6 speaker system installed. It included a mid-range 5-1/4" speaker (Nokia) under the arm rest in the front doors with a 1" tweeter (Nokia) in the upper front doors. It also had a 4"x6" rear speaker (Blaupunkt) under the rear window on each side.

The factory wires for the speakers in my car are as follows (wires connected to the speakers or factory colored wires run):
- Front left negative = brown/white
- Front left positive = white
- Front right negative = brown/black
- Front right positive = black
- Rear left negative = brown/yellow
- Rear left positive = yellow
- Rear right negative = brown/red
- Rear right positive = red
- Power from ignition = green
- 12 volt constant power (for head unit memory when car is off) = red
- Ground = brown (2 wires tied together)
- Power antenna = red/black

The factory door speakers (5-1/4") connect via a single quick-disconnect connector on the outside of the speaker mounting panel. This connector sends signal to the 5-1/4" speaker. Once you remove the speaker mounting panel that houses the 5-1/4" speaker, you can see that the speaker wires that connect to the 5-1/4" speaker have an in-line mid-pass filter.

The factory 1" tweeter speakers connect via 2 brown wires (not to be confused with the earlier stated ground) that run into the top of the door. I did not trace these wires as I did not need them and as such, I did not use them in my new install.

So I’m fitting the new DAB Bremen and also have a 6 speaker system the car wiring at the radio is exactly as you described except I found another connector unattached (see rhs of photo) I guessed this was for a “booster” and left it alone noting that it was connected to one of the 2 brown ground wires into radio connector and likely linked through the permanent red live (2 red wires into unused connector.
My problem is correct coloured wires in loom for rear speakers (which worked fine) but both front speakers had same colour Red +ve and Brown/Red -ve from door loom (and didn’t work when speaker attached).
Any idea how/why front speaker wires enter car loom at radio with correct colours and arrive from door loom with incorrect ones. I looked over the wiring diagrams in Porsche Workshop manual and found no clues.
Any help greatly appreciated. I should mention the car originally came with the Blaupunkt Symphony M327 option and the same option ref is noted on the wiring diagram for a CD changer!

ramius665

Looking at your picture above, the connector you identified is the power connector for the factory amplifiers if your car had the M490/M494 option.

As far as your question about speaker wiring, there are 14 pin connectors at each door for the mirrors/locks/alarm/speakers/etc. I’m looking at the factory wiring diagram right now and it appears you either mis-identified the wiring colors, or someone has re-wired the door speakers. The correct wires for the front left are White and Brown/White, the front right are Black and Brown/Black. At the 14 pin connector at the door, they continue to a 4 pin connector where it splits and adds Red and Brown/Red for the tweeters.

968joy

Thanks for your reply. Where I was going wrong was temporarily using the door tweeters rather than the main door speaker connectors! All resolved now thanks and enjoying the Blaupunkt Bremen DAB

odurandina

2 rules and TWO rules only:
1. All the old garbage is, well: old
Forget the stock doorcard/behind the seat architecture:
Hit hard, go BIG or go home: oversize, super high quality transducers
woofer + midrange + tweeter doors but keep the low mid-bass
out of the doors to reduce their load, and let the HUGE mid-bass units
you're gonna run behind the seats carry 97% of the mid-bass workload.

2. Subwoofer: The 968's cabin requires a SINGLE transducer.
2 transducers unless a back to back [out of phase] setup just fight each other
and gum up the works.
Get the best amp 10" transducer combo you can buy.
BOOM BOOM BA-BAMM BOOM!