Ohm switch on back of receivers

Systems
Systems Posts: 14,873
edited March 2002 in Technical/Setup
Some receivers have a 4 ohm/8 ohm switch & some have a 6 ohm/8 ohm switch. I thought that the lowest ohm switch would let you get more current, since the lower ohm spkrs require more power. But someone told me that the lower ohm switch actually reduces your wattage as a way to make sure that you don't overload your receiver. Another person said that equipment testers for Sound & Vision like to set the switch to 8 ohm even when using 4 ohm spkrs because it allowed them to get more juice. Even though there are some good receivers out there that have this feaure, it sounds to me like the presence of such a switch is a warning sign, indicating that the receiver has liberally rated power, & you should probably get seperates if you want to drive, for example, Polk LSi's. This is just a matter of curiousity to me, I am not wavering on buying anything that depends on the responses (if any) that I get. But it's buggin' me, so I thought I'd toss it into the forum. Thanks.
Testing
Testing
Testing
Post edited by Unknown User on

Comments

  • axeman
    axeman Posts: 170
    edited March 2002
    Ohm's law dictates that current is inversely proportional to resistance, hence, the lower the resistance(ohms), the higher current flow allowed through the conductor, which is your speaker coil.

    A good rule of thumb is that you can always go higher on your speaker impedence over what your amp/receiver is rated, but never go lower as damage could result to the speaker. Remember though, the higher you go on your speaker impedence, the less current, and subsequently volume level you will have out of your speakers.

    Hope this helps.

    Rock On,
    Joe
  • jcaut
    jcaut Posts: 1,849
    edited March 2002
    A few of us talked about this a couple of days ago. Check out this thread: http://clubpolk.polkaudio.com/forum/showthread.php?s=&threadid=2703

    Given a receiver with a 4 / 8 Ohm switch: Setting the switch to 4 Ohms is not going to make the receiver itself, any more powerful. What it IS going to do is allow the receiver to deliver higher current to the (lower impedence) speakers while keeping the overall power output within safe operating limits. Setting the switch to the 8 Ohm position should ALLOW higher output, but if you're using 4 (or even 6) Ohm speakers, the receiver MIGHT get hot and shut down--- Or be damaged.

    I think that if you're considering LSi's, then it's time to look for a good separate power amp, or at least a "premium" receiver.
    Jason
  • joe logston
    joe logston Posts: 882
    edited March 2002
    i thank that all receivers are under powered, wend you turn your receiver up to all most clipping most of the power is going to botten end and the highs gives you that the receiver effect, where it starts to fatigue your ears, and you cant listen to long. thats way i want a separate amp or amps, but if you run a sub out of lfe your receiver works a lot less because the bottem octive on frequency range takes most of the power, and letting the sub handle that part of it will give your receiver better control in the highs & mids on a 8, 6, or 4 ohm spearker,, most all of speakers fluxute there impedence, wend they say that it is a 6 ohms speaker all that is, is an average , it could be from 9 ohms to 3 ohms whitch is a average of 6 ohms or 11 ohms to 5 ohms is a 8 ohm speaker. so for my self i like a lot of power. that way you know that the speaker is not starving for power.
    . rt-7 mains
    rt-20p surounds
    cs-400i front center
    cs-350 ls rear center
    2 energy take 5, efects
    2- psw-650 , subs
    1- 15" audiosource sub

    lets all go to the next ces.
  • sgtgto
    sgtgto Posts: 310
    edited March 2002
    Hi:

    Set the receiver ohms switch to match your speaker impedance as close as possible. For a 8 ohm speaker set it to 8, for a 6 set it to 6. If you have a 6 ohm speaker and your receiver has a 4 or 8 ohm switch set it to 8.

    Remember, a speaker is a transducer. It doesn't demand anything, it only works with what it is sent in the way of a signal.

    Gary
  • joe logston
    joe logston Posts: 882
    edited March 2002
    most drivers are blown because the amp cant give your speaker anough power wend truned up to loud, so it clisps and you blow a driver. if you had more power it would not happin. so your transducer needs the power wend truned up loud.
    . rt-7 mains
    rt-20p surounds
    cs-400i front center
    cs-350 ls rear center
    2 energy take 5, efects
    2- psw-650 , subs
    1- 15" audiosource sub

    lets all go to the next ces.
  • SONYTHEATER
    SONYTHEATER Posts: 27
    edited March 2002
    The selector switch on the back is for ( UL ) testing. When a recever is tested by UL this switch set at the 4ohm setting delevers less current (and yes it can limit your performance) and allows the amp or reciver to run cooler. As far as damageing your reciver with a low restance speaker I wouldent really worry about it to much if your useing farley decent gear. I myself have ran 2ohm loads at full tilt with no problems but I am also useing a pretty damn good recever.
    If you wont to get really in depth on the topic go to home theater fourm.com and get regestered its free and you can find a ton of info there on almost anything.
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited March 2002
    Originally posted by SONYTHEATER
    farley decent gear

    Hmmm, 'sonytheater' and 'fairly decent gear'....

    Contradiction in terms?

    Cheers,
    Russ
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
  • SONYTHEATER
    SONYTHEATER Posts: 27
    edited March 2002
    EDIT (by -justin-)
    PROFANITY: "Abusive or vulgar language, the use of abusive or vulgar language.”

    We don’t need any of this, and if I see it again, you will not be welcome back to our forum.
  • joe logston
    joe logston Posts: 882
    edited March 2002
    what did you do to sony theater russ the post you gave him was not that bad, i been hammerd a lot worse, and i didnt cuss no one out.
    . rt-7 mains
    rt-20p surounds
    cs-400i front center
    cs-350 ls rear center
    2 energy take 5, efects
    2- psw-650 , subs
    1- 15" audiosource sub

    lets all go to the next ces.
  • RuSsMaN
    RuSsMaN Posts: 17,987
    edited March 2002
    Sonytheater, tell us how you REALLY feel!!!

    Cheers,
    Russ
    Check your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service.
  • pensacola
    pensacola Posts: 269
    edited March 2002
    >>Sonytheater, tell us how you REALLY feel!!!

    Anyone who CARES how he feels... raise your hand.:rolleyes:

    Give War A Chance
  • cruiser3
    cruiser3 Posts: 47
    edited March 2002
    More fiber in their diets might help...........
    Onkyo 696 receiver, Panasonic DVD RV31U,Polk RM6600 w/ 350 sub (rti28's 2nd zone), JVC Dual tape deck, MMF-2.1 Turntable, JVC 5010 CD R. ((its simple, its cheap, it works))
  • kanicker
    kanicker Posts: 86
    edited March 2002
    Over-reaction to be sure. But c'mon... razzing a new guy for claiming his gear is fairly decent? I'd say Sony is fairly decent. Thats a very small compliment...
This discussion has been closed.