240sx audio wiring

Discussion in 'OT Technology' started by perfeng702, May 29, 2007.

  1. perfeng702

    perfeng702 Active Member

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    I just purchased another 240sx that had a Pioneer H/U already installed. The factory Clarion amps are still being utilized. The conversion harness uses some resistor looking things (no gain adjustment) to convert the speaker level output to line level for the factory amps to use.

    I have since removed the pre-installed low end Pioneer H/U and replaced it with my Premier H/U. With the current setup, there quite a bit of electrical noise that can be heard. I assume it's from the use of the ghetto speaker level -> line level conversion. The H/U has front, rear, and sub line level outs. Is it possible to modify the conversion harness and add male RCA's to plug directly into the H/U? Would that work better than a PAC ROEM-NIS2?
     
  2. twistid

    twistid Banged By Super Models Moderator

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    pac products are not ghetto... my guess is it's the install of the new deck, since the old deck worked fine... make sure you have a good ground.
     
  3. perfeng702

    perfeng702 Active Member

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    No no... I mean my option is either getting the Pac or wiring in the RCA plugs. The system doesn't have either right now. It is currently just using some Install Edge resistor things to convert the signal. The system has the same amount of noise with both H/Us. I have not modified any of the wiring yet because both H/Us share the same style plug. I would like to utilize both the factory Clarion amps. I would like to know if they will accept the line level output from the H/U.

    Update: After some more research, it appears that the Install Edge thingys aren't converting the signal, they are IEC CAP199s. They apparently filter frequencies below 200hz. That means the factory amps are receiving a speaker level input right?
     
  4. perfeng702

    perfeng702 Active Member

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    So here's the summary.

    I want to retain the factory amps. The factory amps interface as a part of the standard wiring harness. Do I:

    1. Use PAC ROEM-NIS2 to convert the speaker level output from the H/U to line level for the factory amps. (H/U Speaker Level -> PAC -> Line Level -> Amp)

    or

    2. Splice in male RCA's to connect the factory amps directly to the line level output of the H/U. (H/U Line Level -> Amp)

    I know, normally, option 2 would be the best choice, however, I don't know whether or not the factory amps require some kind of gain/voltage adjusted signal. Can I just splice in male RCAs? Would the center prong be + or -?

    These are the factory amps:

    http://www.auctiva.com/hostedimages...2,41612279&formats=0,0,0,0,0,0,0,0,0&format=0
     
    Last edited: May 29, 2007
  5. wabash9000

    wabash9000 Active Member

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    the factory amps suck. if you are going to run with them then hook the inputs of the amp to a non amped source. aka if your headunit has rca jacks on the back. what I did is what I recomend. run new wire. i ripped out the factory amps and then ran new 16ga stinger wire through the center consol in to the trunk where the amps were then I used a factory service manual to find the correct wires on the amp wiring harness to hook the wire up to. now my speakers are running on the amp in the head unit. i like to keep the wireing simple. right now you are taking your source. amplifing it. deamplifiying it. then amplifing it bofore it comes out the speakers. eleminate the factory amps and you will be glad you did. if you want I can take pictures of my removal and make you a list of the pinouts for the factory amps.

    if that is too much for you the do option 2. option one just plan sucks.
     

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