Newbie question about impedence

Discussion in 'Speakers & Subwoofers' started by Billy Z, Sep 20, 2003.

  1. Billy Z

    Billy Z Auditioning

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    I just bought the Polk Lsi Series (lsi15,lsiC,2xlsiFX) for my home theater and just noticed that they are rated at 4ohms. Problem is my A/V reciever Denon 5800 is rated from 6ohms to 16ohms. Will there be any problems if I hook them up to this receiver? Thanks in advance
     
  2. Wayne A. Pflughaupt

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    You may find that the speakers will send the Denon into protection, especially during loud passages. If you’ve tried it and everything works fine, then don’t worry about it.

    Regards,
    Wayne A. Pflughaupt
     
  3. Billy Z

    Billy Z Auditioning

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    I haven't hooked them up yet. But if it does set off the protection circuit system is there any way around it without buying new speakers or a new receiver? It has ratings for 6 ohms at 200watts a channel. I wished I would have known about this site awhile ago.
     
  4. Wayne A. Pflughaupt

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    A heavy-duty, 100-watt 8-ohm resistor connected in series will get you a 6-ohm load, I think. You should be okay then. It’s not hard to find heavy duty resistors at electronics hobby stores.

    Regards,
    Wayne A. Pflughaupt
     
  5. GregGreenman

    GregGreenman Auditioning

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    A 2 ohm resistor wired in series with a 4 ohm speaker will give you a nominal 6 ohm resistance. Resistances wired in series
    are additive.

    Also remember that the 4 ohm rating of the speaker is an average value - the actual impedance varies with frequency.
     
  6. Wayne A. Pflughaupt

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    Greg is correct – thanks for the correction. [​IMG]

    Regards,
    Wayne A. Pflughaupt
     
  7. Chu Gai

    Chu Gai Lead Actor

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    Keep in mind that adding a resistor in-line with the speaker will also drop your speaker's effective efficiency and meaning you'll now need additional power to produce the same SPL. Hence the same arbitrary setting on your receiver will result in lower volumes. Furthermore the insertion of a resistor will affect the speaker's frequency response acting in effect as an equalizer. So yes, you can add a resistor but it's not the greatest idea in the world.
    I'd try it without as Wayne first suggested.
     

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