Speakers Ohm Still confussed

Discussion in 'Receivers and amplifiers' started by capu57, May 25, 2007.

  1. capu57

    capu57 Member

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    Hi there I have the brand new Sony STR-DA5200ES receiver and will be getting some Martin Logan Speakers. The speakers I am looking at are rated at 4 ohms and my receiver can be set at either 8 or 4 ohms. I know it all has to do with how much electrical resistance there is on the amp of the receiver. But every site I have tried to read about it they all get very technical and don't give basic answers. Well I have a few questions about this.

    1. Would I actually get better performance out of the receiver and
    speakers if I do set it to 4 ohms.

    2. What is the main advantage to setting it to 4 or 8 ohms in terms
    that the average person would understand.

    3. A friend told me if I have 4 ohm speakers and can set my
    receiver also to 4 ohms that I would be able to be able to run
    my speakers louder and put less wear and tear on my receiver is
    this true?

    4. Also what would be the best way to hook up a speaker than can be bi-wired in this circumstance would it be best to do 1 of the following and please explain why.
    single wire 4 ohms
    single wire 8 ohms
    bi-wire 4 ohms
    bi-wire 8 ohms
    Thank you to anyone who can answer any of these question and I will admit I do work in the home theater industry as an installer and I am not a moron but the whole ohms thing just confuses me.
     
  2. JVC

    JVC Active member

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    1 - yes, you should
    2 - If you try to drive 4 ohm speakers, with an 8 ohm receiver, you can cause the receiver to overheat and go into "Protect Mode", and it will shut off. Especially at loud volumes. If something happens to be wrong with the "Protect Mode" sensor, you could fry your receiver. Not saying you would, but you definitely could. Better to not take the chance!
    3 - yes
    4 - don't know anything about bi-wiring........ sorry :eek:)
    Good luck!
     
  3. capu57

    capu57 Member

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    Thank you for the reply as for Bi-Wire that is when you have a speaker with 4 speaker wire terminals 2 + and 2 - and you run 1 set of speaker wire to 1 set of terminals and the other wire to the other set. On the speaker if you buy this kind you will have what they call a bridge or shorting bar. If you bi-wire you are supposed to remove this or it could cause the speaker signal to travel back on 1 wire and do damage to your receiver and sometime the receiver will just shut down as soon as you start until you fix the problem. Basically it the same thing as having to two bare speaker wires touching each other right behind your receiver. Of course if you only use 1 wire to your speaker the shorting bar or bridge should be in place other wise you're only using 1/2 of your speaker. The advantage to this is that you keep your high freq and low freq on 2 separate lines to provide clearer sound. Here is an example of Bi-Wire [​IMG]
    and here is an example of single wire on a bi-wire speaker
    [​IMG]
    and the connections on a single wire speaker
    [​IMG]
     
  4. JVC

    JVC Active member

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    Thanks for the illustration........... :eek:)
     
  5. capu57

    capu57 Member

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    for the picture of the first bi-wire speaker you dont have to have 2 amps some people just double up the wire on the amp end so there would be 2 wires in lets says right front speaker 1 and 2 wires in left front speaker 1. And on the other it would be just like the picture. Idealy its best to run two amps but it is not necissary.
     

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