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matching ohms?

Discussion in 'Amps and Cabs [BG]' started by ikickuintheballs, Jul 30, 2000.


  1. If I'm using a combo amp that's at 4ohms would it matter that I hook it up to my cab that's 8 ohms? Would it damage my cab?
     
  2. Matthias

    Matthias

    May 30, 2000
    Vienna, Austria
    If the amp of your combo is rated at 4Ohms and the internal speaker is also rated at 4Ohms you can not add another speaker, because the overall impedance would then be below 4Ohm, wich can damage the amp.
    If the internal speaker is rated at 8Ohms you can add another 8Ohm speaker (8Ohms and 8Ohms is 4Ohms in total, because you have to add the reciproke values: 1/8+1/8=1/4)

    hope that helps,
    Matthias
     
  3. jcadmus

    jcadmus

    Apr 2, 2000
    Very nice, clear answer from Matthias on this issue. If you want to know more, there's a very good article on this issue in the latest edition of Bass Player magazine (the one with Tony Kanal of No Doubt on the cover).
     
  4. Thx for the help =) it's very much appreciated.

    -Willz
     
  5. High Camp

    High Camp Supporting Member

    Oct 3, 2013
    Netherlands
    I wanted to revive this very, very old thread.
    Why?
    Because apparantly, even before the Euro was introduced (and dinosaurs still roamed the earth), this topic has been discussed to the death!
    I want to dare anybody to count the number of different threads, covering this topic.
    The winner will be given everlasting fame!
    The loser: a manual to the "search" button.;)
     
  6. DiabolusInMusic

    DiabolusInMusic Functionless Art is Merely Tolerated Vandalism Gold Supporting Member

    Basically a combo is just an amp and cab packed into one solid unit, in this instance the amp is capable of 4 ohms and the internal cab is 4 ohms, this means you cannot add an additional load without damaging the amp.

    The amp is not capable of a load larger than 4 ohms, the 8 ohm extension cab is fine only if you disconnect the internal 4 ohm cabinet from the amp. I do not know the amp in question so I do not know if this is possible, it is not usually possible.

    If you would like a more technical explanation somebody can definitely give you one.
     
  7. High Camp

    High Camp Supporting Member

    Oct 3, 2013
    Netherlands
    Sorry, but that's not what I meant. I know about the difference between 4 and 8 ohms.
    It's just that about every other day a new thread appears, asking about impedance.
    >> This thread was from the year 2000!
    The question was answered 14 years ago!
    That's my point! ;)
     
    DiabolusInMusic likes this.
  8. DiabolusInMusic

    DiabolusInMusic Functionless Art is Merely Tolerated Vandalism Gold Supporting Member

    Ahhhh.. still new here. You just start to ignore the threads, anything with "for metal" in the title gets ignored by me as well. I personally feel the word "best" should be added to the censored words.
     
    High Camp likes this.
  9. BassmanPaul

    BassmanPaul Gold Supporting Member

    Aug 25, 2007
    Toronto Ontario Canada
    The zombies are out in force this week and it's not even Halloween!!!

    :D
     
    High Camp likes this.