Stereo Questions - Ign. Toggle Switch , Grounding

Discussion in 'Audio' started by canuck222, May 1, 2014.

  1. canuck222

    canuck222 vroom, vroom... Supporting Member

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    I'm putting together the pieces for a relatively inexpensive hidden stereo system with the intention to keep the factory am radio functional. The hidden radio will be an Alpine head unit located in the trunk controlled via their RF Marine Remote control from inside the car. I've sketched out an image at the following link for a rough reference to my questions:

    http://i5.photobucket.com/albums/y197/alpala/CometStereo1.jpg

    1) What power source at the fuse box is suggested to use for the ignition lighted toggle switch? Noting that I want an always hot wire going to the radio, so I can run the radio even if the car is off. - i.e. I take it to the drive-in movie and want the radio but not keep the key on accessory. The toggle switch will ensure that I can kill the radio when I park the car at home.

    2) What do you recommend for grounding location in the trunk?

    3) Are the wire sizes realistic? I'm not sure about the amp in the future but want to provision for it and not have to rerun wires, especially if I find that the head unit is insufficient and the rear speakers need more juice + sub install.

    http://www.alpine-usa.com/product/view/ute-42bt - head unit

    http://www.alpine-usa.com/product/view/rue-m1rf - RF Marine Remote


    Thanks for your consideration and input.
     
  2. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    Looks like a plan to me. As far as grounding - any place in the trunk floor or as short a lead as possible to any solid place in the trunk. Also, same gauge wire to grn as feed cable.
     
  3. mercgt73

    mercgt73 Member

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    This is almost exactly what we did in my dad's 1964 Buick convertible for the purpose of car shows. But his setup is a little different. Let me review the drawings we had for his project and post up some feedback. Maybe it will give you some ideas, or not. It's up to you.

    For my dad, he wanted:
    1. To retain the factory AM radio and have it use the factory single speaker. (this was easy, don't mess with it)
    2. To have a 10-disc CD changer and new style head unit hidden in the trunk.
    3. To use amplified front kick panel speakers and amplified 6x9s in boxes tucked away in the trunk / soft top storage area. (convertibles are loud, so he needed some umph).
    4. To have the head unit be controlled from the drivers seat and have a display panel to show him the time, volume, station, etc.
    5. To be able to run the new head unit with the key off.
    6. To have the head unit power (via the amp) the 4 interior speakers OR send the audio (no amp) to a drive in movie theatre speaker stand next to the driver's door (for playing old time commercials)
    7. To have the head unit and amp operate off of a remote control so that he could turn the drive-in speaker on/off at car shows without getting up from his chair.

    I will sketch up the wiring diagram and post it so you can look at it. I will be at the shop tomorrow and I can snap some pictures of the trunk for you just to give you an idea how we mounted the trunk head unit and amp.
     
    Last edited: May 2, 2014
  4. canuck222

    canuck222 vroom, vroom... Supporting Member

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    Thanks, might give me some ideas.
     
  5. mercgt73

    mercgt73 Member

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    Here are the pics of the trunk stuff. The 6x9s are tucked in behind the carpeted panel. Also is a pic of the radio/cd changer control unit.

    [​IMG]

    [​IMG]

    [​IMG]

    Here's a quick recap of how we wired it. Similar to yours, my dad has a remote controlled relay that is fed by 12+ Constant for the head unit. He can supply and remove power from the head unit without the ignition being in the run position. Next, all 4 interior speakers are run by the amp, which has a toggle switch on the blue "amp on" wire from the head unit. This allows him to either run the amplified speakers OR run a drive in theater speaker outside the vehicle (via a pair of speaker wires). In his CD changer, he has 1 or 2 CDs which are just 1960's drive in theater commercials.

    So, to help answer your original questions:
    1) My dad chose to simply run a new constant 12V+ from the solenoid for his head unit, rather than splice into the original harness. You may want to do that, it's up to you. That is what I recommended he do, just to make it easier and to keep it separate.

    2) In the trunk we found a sturdy body support and simply drilled a hole, cleaned the paint off, used a star washer and grounded the head unit and amp right there. We put some dielectric grease on the eyelets to keep oxidation to a minimum.

    3) For the head unit we simply used a feed wire 1 size larger than the pigtail that the head unit came with, since were adding more distance. We put a fuse on the solenoid feed end, and also kept the radio fuse inline in the trunk. For the amp, we used a amplifier feed circuit sizing guide, like the one here: http://www.crutchfield.com/S-KhDjVrygPoz/learn/learningcenter/car/cable_gauge_chart.html

    Hope this helps!
     
  6. canuck222

    canuck222 vroom, vroom... Supporting Member

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    Thats a clean install and gives me a few ideas. Ill update my diagram and post some pics of the finished setup in a month or so.
     

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