beginner wiring lesson....

Discussion in 'Home Theater Projects' started by Cam McFarland, Jun 26, 2004.

  1. Cam McFarland

    Cam McFarland Supporting Actor

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    I have 2 subs...both, dual 4ohm VC.

    If I hook up one wire (each) red/black to +/- of both V coils on one sub, and then twist those red/black together, that's a 2ohm load the amp sees, right?

    Then I do same to other sub & twist the final red/black from
    "each" sub together, its back to a 4ohm load, right?

    What if I dont twist the 2 final red/black together, but instead hook them up individually to the mono sub amp...is the amp seeing (2) 2ohm loads, or is it still seeing a 4ohm load.


    Man, I hope that was clear enough for somebody to answer.


    - Cam
     
  2. StephenHa

    StephenHa Second Unit

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    basically it sounds like your just paralleling the voice coils, but then you need to run the subs in series to raise the impedance (one speaker positive to amp, negative to second sub positive, negative to amp)otherwise the amp will see a 1 ohm load (not usually healthy in a home theater type product)
     
  3. Cam McFarland

    Cam McFarland Supporting Actor

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    Sorry, actually this is for my truck & I didnt know if i would be seeing a 2ohm or 4ohm load, I was looking for a 2ohm load at the amp if I could get it.

    If I am paralleling the voice coils, that would make each sub 2ohms, right?

    Would it be 2ohm the way you stated?
     
  4. StephenHa

    StephenHa Second Unit

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    by paralleling the voice coils you create 2 2 ohm loads, what you can do to get a 2 ohm load is series wire the voice coils (like I said to do to the subs) then parallel the subs
     
  5. Allen Ross

    Allen Ross Supporting Actor

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    series wiring the VCs would get 2 8 ohm loads which is 4 when paralleled
     
  6. Brian Fellmeth

    Brian Fellmeth Supporting Actor

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    In other words, your choices are 1 ohm, 4(2 ways to get to 4), or 16. 2 is not an option, unless you only use one VC from each driver.
     
  7. Cam McFarland

    Cam McFarland Supporting Actor

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    I didnt think I could get to 2ohms, but I had to ask.

    Anybody care to give a little more involved "best" way to
    do the wiring without using either the word "series" or
    "parallel".

    Or, at least tell me that this would be a correct way (or not) to get 4ohms.....


    Thanks guys.......
     
  8. ThomasW

    ThomasW Cinematographer

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    Cam,

    Color me confused, but your profile says Occupation -electrical designer.......... [​IMG]

    Read this LINK to learn what series/parallel wiring is.
     
  9. Brian Fellmeth

    Brian Fellmeth Supporting Actor

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    Take one sub, it has 2 red and 2 black lugs.Connect red to red and black to black on the lugs of the sub. Then do the same with the other sub. Run the amp red to the red pair on one sub. Run the black amp wire to the black pair of the other sub. Then wire the black of the first sub to the red of the second. This will end up with the load of an single VC, which you said was 4.
     
  10. Cam McFarland

    Cam McFarland Supporting Actor

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    Hey Thomas, I understand & appreciate your confusion, but hey, was that really easier than a yes or no on your part.

    Thanks for the link, I have plenty of "links" & hard copies
    of similar info, but just wanted some validation...[​IMG]


    Any body care to ANSWER these questions with simply a
    yes/no response, if no then let me know individually which is right/wrong.

     
  11. MichaelAngelo

    MichaelAngelo Stunt Coordinator

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    If I hook up one wire (each) red/black to +/- of both V coils on one sub, and then twist those red/black together, that's a 2ohm load the amp sees, right?

    Then I do same to other sub & twist the final red/black from
    "each" sub together, its back to a 4ohm load, right?




    Wrong. Cam, you have the first part down- dual 4 ohm VC, red to pos blk to neg, the black wires together +the red wires together == 2 ohm load. Right. Now if you do this with two speakers, and tie THEIR red and black wires together, it will halve again, just like the first time, because you're doing the same thing, pos+pos and neg+neg, just with 2 drivers instead of 2 VC.

    Now, if you wire the 2 VC on the driver like you said(pos/pos and neg/neg) this is 2ohm. if you have 2 drivers, and just wire the 2 sets of pos together and the 2 sets of neg together, and hook it to the amp like that, it will present a 1 ohm load to the amp. If, however, you take the pos set of leads from one driver, hook that to the amp, take the neg of that driver and hook it to the pos terminal of the second driver, and connect the second drivers neg to the amp, this will result in a 4 ohm load to the amp, otherwise known as series wiring.
    Hope this helps. [​IMG]__~

    BTW, I just checked the link Thomas provided. Take a look at the first couple of images-- they show what series vs parallel wiring is-- and a picture, in this case, is worth ~200 words. [​IMG]
     
  12. Cam McFarland

    Cam McFarland Supporting Actor

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    Thanks again MA.......[​IMG]


    So...both pos. from one driver to amp pos...both neg of that driver to both pos of second driver....both second drivers neg back to amp neg.....right?
     
  13. ThomasW

    ThomasW Cinematographer

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  14. Brian Fellmeth

    Brian Fellmeth Supporting Actor

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    Yes, that will give you 4 ohms (or whatever a single voice coils impedance is). Thomas W's diagram is the other way to get 4 ohms. Use either one, the amp won't know the difference and it will sound the same.
     
  15. Cam McFarland

    Cam McFarland Supporting Actor

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    Thanks guys, know I am a pain.

    I saw the diagrams, & they differed from the way I looked at it.
    Both subs will be in seperate boxes underneath the back seat, & I am trying to find out the easieast way to do the wiring "between" the boxes, but I guess it wont make any difference.
     

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