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Botched nokia dsp and speaker polarity question

pietrzj

Well-known member
Joined
19 Mar 2014
Messages
309
A previous owner has had the nokia dsp system bypassed, but I am not happy with the way it was done and would like to see what a working dsp system is like and would like the car more original.

If the original setup is not acceptable for occasional use (I am not an ICE enthusiast when I have that incredible flat 6 sound running) then I will bypass it properly.

On stripping the door panels and checking over the nokia speaker box connections, there are 3 pairs of wires for the 3 speakers. Each of the three door speakers having a green (-) and a green & black (+) wire. According to the bentley manual wiring diagram the biggest of the three (deep) speakers, has its own dedicated pair - Pin 1 & 2, which ties up with what I have found, and the mid-range and high-range speakers are connected together at the connector Pin 3 & 4 on the nokia speaker-box - sharing a pair back to the underseat unit.

Interestingly the mid and high speakers are connected pos (+) to neg (-) on the original wiring so one is affectively reverse polarity. However, the original wiring has been snipped at the connector in such a way as I can't tell whether it is the mid speaker or the high speaker (sometimes called a tweeter) that has had its polarity deliberately reversed in the original wiring. The image shows the pin connector 3 & 4 both having gn & gn/bk wires connected at the bullet connector.

Anyone know which speaker is more likely to be deliberately polarity reversed, the mid range or the high range?

JanP
 

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Botched nokia dsp and speaker polarity :eh!:
 
Using google it looks like the tweeter is mainly the one deliberately reversed to avoid flat spots - whatever they are.

Started tidying up the wiring in the door units - bit fiddly, but all short leads have been repaired with additional sections soldered on and sealed up with rubber sleeves.

Just need to double check the tweeter polarity at the speaker end, but will have to remove the door panel to do that - which I have to do as I am removing the door itself to replace the hinge bushes (see other post).

will post more pics soon.
 
tinned up end wires at the connector
 

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sleeved up soldered extensions (didn't have the right coloured wires, but kept to a scheme of single or multi coloured insulation
 

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