Speaker wire next to Electrical wire.

Discussion in 'Beginners, General Questions' started by marc_manny, Jan 21, 2004.

  1. marc_manny

    marc_manny Stunt Coordinator

    Joined:
    Nov 25, 2003
    Messages:
    55
    Likes Received:
    0
    I am going to be running my speaker wire into my basement and across the basement ceiling. It will at times run next to electrical wire. Should I buy shielded wire? If so where is a good place to pick some up? Will there be a noticeable hum?

    Marc
     
  2. Kevin G.

    Kevin G. Second Unit

    Joined:
    Sep 30, 2003
    Messages:
    403
    Likes Received:
    0
    I researched this a little when I wired my upstairs for sound, and was led to believe that if at all possible DO NOT run parallell to any electrical wire. If it needs to come close to electrical wires then cross the wires @ 90 degrees
     
  3. John S

    John S Producer

    Joined:
    Nov 4, 2003
    Messages:
    5,460
    Likes Received:
    0
    correct, try not to run parallel to the wire, try your best to run across it. Sheilded is good too, but expensive.
     
  4. marc_manny

    marc_manny Stunt Coordinator

    Joined:
    Nov 25, 2003
    Messages:
    55
    Likes Received:
    0
    How close can I put the boxes to each other? i.e. the eletrical outlet and the speaker wire connection in the wall?

    Where can I pick up shielded wire?

    Marc
     
  5. Wayne A. Pflughaupt

    Joined:
    Aug 5, 1999
    Messages:
    6,061
    Likes Received:
    25
    Location:
    Katy, TX
    Real Name:
    Wayne
    Marc,

    You said the speaker and electrical would run parallel “at times.” Speaker-level signals are high-level and therefore much more resistant to EMI than line-level signals. It won’t hurt for them to be parallel for short distances – say a few feet – but if it’s longer than that it would be best to find some way to separate them.

    I don’t know of anyone who makes shielded speaker cable. However, you could provide shielding by running either the electrical or speaker cables through conduit.

    As far as installing wall boxes, a couple of feet apart will be fine.

    Regards,
    Wayne A. Pflughaupt
     
  6. John S

    John S Producer

    Joined:
    Nov 4, 2003
    Messages:
    5,460
    Likes Received:
    0
    I believe even Radio Sgack of all people sell it. But I won't swear to that. They make it for places that have unreal amounts of EMI. Large motors and inductors, that sort of thing. Conduit is another option for sure.
     
  7. Chu Gai

    Chu Gai Lead Actor

    Joined:
    Jun 29, 2001
    Messages:
    7,270
    Likes Received:
    1
    To mitigate any potential problems, consider getting speaker wire that's twisted which will severely reduce the inductin of any EMI. Not twisted enough? Tie one end to something stationary and twist the other end with a drill.
     
  8. Iver

    Iver Second Unit

    Joined:
    Sep 23, 2002
    Messages:
    324
    Likes Received:
    0
    If you want an effective shielded cable, you could use coax, but for a long speaker run (over 30 feet w/8 Ohm speaker, 15 w/4 Ohm, 7.5 w/2 Ohm) the narrower varieties of coax might add a bit too much resistance. So you'd want to go with an RG-8 or similar versus RG-58 or RG-59.

    Even better would be a cable with two inner speaker wires and a surrounding shield which you can ground. Something like an XLR line. Again, make sure the load-carrying wire is of a low enough resistance (low enough gauge number) to handle your length/power/speaker resistance.

    But as others have mentioned you're not likely to get such a strong A/C hum that it'll be audible over your speakers. So unless this is an installation you'll really be stuck with, you might want to just go ahead with standard in-wall speaker wire and try to avoid running it near the A/C line as much as possible.
     

Share This Page