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  • Cable question...

    For a one or two foot run, can I use regular 3-pin XLR or must I use DMX type cable?

    This would be from one LED fixture to another.

    Thanks,

    Steve


  • #2

    Age old question I hear sometimes XLR mic cables as a dmx function can cause the fixture to mis communicate or be "jiggy" so to speak due to lag for the digital transfer of information down a cable that wasn't meant for a digital signal. Did you try it? I almost did the other day but said screw it, got the DMX cable out of the trailer.

    Comment


    • stevmac1
      stevmac1 commented
      Editing a comment

      Haven't tried it yet. I'd have to buy or make the DMX shorty cables, but I already have a few short XLRs. 

      steve


  • #3

    It will work, and if you are only doing a short run, you most likely won't have any problems.


    If you're interested in the physics behind using the proper cables, look up Impedance mismatched Transmission Lines.

    In a nutshell, you could have errors do to reflections; the signal travels down the line, and a portion of it is reflected back (much like a ball bouncing off of a wall). This reflected signal can interfere with the intended signal giving you data errors.


    Good judgment comes from experience, and a lot of that comes from bad judgment. -Will Rogershttp://facebook.com/SpitShineRocks

    Comment


    • BillESC
      BillESC commented
      Editing a comment

      Data transmission is subject to lots of interference.  The total cable length, number of connections, termination and transmission ohm rating.

       

      In small systems with less than a hundred feet of total cable length or few connections, the type of cable may not matter.  As systems grow where total length increases and the number of connections grows, just one mic cable in the mix might cause unwanted data loss.

       

      If you buy a high performance sports car and fill it with unleaded, who's to blame when a Kia beats it off the line from a traffic light.  The point is, a mic cable might "save the day" but it is not the right tool for the job.


  • #4
    I would only use XLR in an emergency situation. Even then I would have to think about it long and hard. Nothing is more frustrating than signal issues due to bad cables in your rig. Another lesson I learned the hard way.
    https://www.facebook.com/highvoltagestagelighting

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