Tweeters with low-end sound systems

[bimmer630]

my car is a 1990 two door, built with low-end audio.

Tweeter connections are already there in the doors.

the wires come through the door jamb connector, and connect to pre existing junctions on the kick panel speaker wires… BUT.. the small blue connector for the tweeter fits into the matching female connector on the speaker wire for the POSITIVE side of the speaker. The spade style connector has a matching plug that branches off of the NEGATIVE SIDE of the speaker wiring.
So..
I’m converting the speakers to the “sound system” stuff out of my parts car, no amp, and a old blaupunkt head unit. With those kick panel speakers installed, the tweeters are supposed to connect + side to the post connected to the capacitor on the speaker, and negative connects to the y-cable branch that comes off of the speaker wire.

Issue is, these plugs are reversed, so you can either connect the tweeter to the two existing y-cable branches, which gives the tweeter no Xover, and reversed polarity.

Does polarity not matter on a tweeter?
Did bmw mess up the harnesses on some cars?
why is the wiring even THERE AT ALL for a tweeter on a low end sound vehicle, especially if the connections have nothing to do with the way an amplified “sound system” version is wired?

I ended up cutting the blue plug off of the end of my tweeter wiring and splicing in a speed connector so I could connect the positive side of the tweeter to the capacitor plug on the speaker

[bimmer630]

The harness piece in the picture here is cut out of the donor car, which was wired for an amplifier from the factory. The blue plug is on the negative side of the speaker here as opposed to the positive side of the speaker on the non-amplified system in my car.

[bimmer630]

Random pics

[reelizmpro]

Sure polarity matters with tweeters but remember the cap on the mid is the high pass filter for the tweeter. Being a 1990, BMW revised the wiring in all cars at some point to accommodate premium sound.

All you need to know should be here including the premium sound schematics

https://www.r3vlimited.com/board/for...and-amp-wiring

[bimmer630]

Sure polarity matters with tweeters but remember the cap on the mid is the high pass filter for the tweeter. Being a 1990, BMW revised the wiring in all cars at some point to accommodate premium sound.

All you need to know should be here including the premium sound schematics

https://www.r3vlimited.com/board/for...and-amp-wiring

well that’s my whole point. The way BMW wired this car, the tweeter HAS to be wired reversed.
They put the pigtails in there to accommodate tweeter wiring, but the rest of the car is NOT set up to accept high end sound. The wiring going back to the amplifier area is not there, the wires are all different colors…
it’s all very confusing.. I don’t know WHAT they were trying to accomplish with the way these were wired.

there’s also a brown/black wire behind each kick panel speaker which connects to nothing..


I looked through all of the posts on R3v that I could find and nothing matches what my car has. Nothing in any google searching has shown me anything that relates to what I’m seeing on my car, either.

It doesn’t really matter, it’s in there and it sounds good. It’s just a curiosity to me.. in that I had to cut and move connectors around to make it work properly.