Speaker wiring help.

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by rockon1, Aug 31, 2006.

  1. rockon1

    rockon1 Member

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    Trying to wire up my 4x12 cab with a switch so I can change from 4 to 16 ohms quickly.(Im running 4 -16 ohm speakers). Can this be accomplished with a DPDT switch? Having a hard time on paper...Thanks Bob
     
  2. shooto

    shooto Supporting Member

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    well, I dont think you can run 16 and 4 - if you wire them in parallel you've got a 4 ohm load- if you wire them parallel/series you've got a 16 ohm load-- you can do a stereo/mono switching using a dpdt switch but you would run 4 ohm mono and 8 ohm stereo....just switching from 4 to 16 though?...don't think it's possible-
     
  3. LZ_69

    LZ_69 Member

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    I dont think a dpdt would work, but a on-on 3pdt would.

    Here's a couple diagrams:

    Series(4ohms): http://home.earthlink.net/~iktoblikto/series.pdf

    Parallel Series(16ohms):http://home.earthlink.net/~iktoblikto/parallel_series.pdf

    Now looking at those two diagrams you can see that these share a few common wires so if you cab is wired differently start by changing the wiring to match the series diagram but you can leave out the two wires that go from the bottom speakers to the top speakers.

    Here's what your switch will look like ABC are the poles and the 123 are the terminals:
    A B C
    1 1 1 series side
    2 2 2 center
    3 3 3 parallel series side

    This is how you should wire it up:
    A1) connect to the bottom left speakers negative.
    A2) connect to the top left speakers positive.
    A3) connect to the bottom left speakers postive.

    B1) connect to the bottom right speakers postive
    B2) connect to the top right speakers negative.
    B3) connect to the bottom right speakers negative.

    C1) is not used
    C2) conect to bottom right speakers postive.
    C3) connect to the bottom left speakers negative.

    good luck.
     
  4. shooto

    shooto Supporting Member

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    series wiring would give him a 64 ohm load, no?
     
  5. rockon1

    rockon1 Member

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    Yes it would! Thanks guys for the input. Much appreciated. I hate to say it but I had an idea to run "stereo" with two pairs wired in parallel to two serperate jacks and then add a switch for 16 ohm mono operation. That woud give me a lot more flexabilty. I'd have 8 ohms a "side" and can run them both to my head at 4 ohms. OR run two amps into the same cab with an ABY box. Or switch it to 16 ohms mono.Also a switch to 16 ohms mono should be fairly simple. Thanks again Bob
     
  6. John Phillips

    John Phillips Member

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    4/16 ohm (series/parallel using two 8-ohm speakers or pairs) switching can very definitely be done with a DPDT switch.

    Labeling the six pins of the DPDT like this:

    A B C
    D E F

    And calling each 8-ohm pair a 'speaker', connect:

    Jack+ to speaker 1+ and to A
    Jack- to speaker 2- and to D
    Speaker 1- to E
    Speaker 2+ to B
    B to F, or E to C (Doesn't matter which - you can also do C to F but it's marginally less reliable. For absolutely maximum reliability connect both B-F and E-C, but make sure the wires don't touch each other.)

    You have parallel wiring when the switch is connecting A-B and D-E, and series when it's B-C and E-F.
     
  7. LZ_69

    LZ_69 Member

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    I guess that what happens when you try to answer tech question when you really should be sleeping....here's the proper diagrams:

    Parallel: http://home.earthlink.net/~iktoblikto/parallel.pdf

    Series Parallel: http://home.earthlink.net/~iktoblikto/series_parallel.pdf

    Again there's only 3 wires different so same 3pdt switch I described earlyer will work.

    A B C
    1 1 1 parallel side
    2 2 2 center
    3 3 3 series parallel side

    a1 connect this to the lower left speakers negative
    a2 conect this to the neg side of the imput jack
    a3 connect this to the lower right speaker negative

    b1 connect to the upper left speaker positive
    b2 connect to the upper right speaker positive
    b3 unconnected

    c1 connect this to the upper right speaker negative
    c2 connect this to the upper left speakers negative
    c3 connect this to the upper right speaker postive

    Should work out better?
     

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