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Different Speaker Impedence in a stereo amp??

Discussion in 'Amps and Cabs [BG]' started by thewanderer24, Jul 31, 2003.


  1. thewanderer24

    thewanderer24

    Apr 29, 2002
    SJ, CA
    Hey folks.

    I have been thinking about overhauling my rig in a major way, and have a few questions.

    What kind of issues do I need to worry about if I am running a stereo PA with an 8 ohm cab on one channel and a 4 ohm cab on the other??

    What about linking an 8 ohm cab and a 4 ohm cab together on the same channel??
     
  2. BruceWane

    BruceWane

    Oct 31, 2002
    Houston, TX
    No issues whatsoever.
    Your total load will be 2.67 ohms. Just make sure the amp is OK with that - most power amps are fine down to 2 ohms on each channel, but are not OK with less than 4 ohms when bridging.
     
  3. mastadulog

    mastadulog

    Jan 13, 2003
    NYC fo sheezy
    can i do the same on a regular bass head?
     
  4. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    There is one issue which may not be a big one in most cases. The 4 Ohms cab will draw more power from the amp so it may be louder than the 8 ohm cab, depending of course on what speakers you're using.

    If the 4 ohm cab is overpowering the 8 ohm, no drama, just turn that side of the power amp down until volume from the 2 cabs are balanced.
     
  5. Petebass

    Petebass

    Dec 22, 2002
    QLD Australia
    Can you run an 8 ohm cab with a 4 from a regular bass head? It depends. A Bass head doesn't usually have 2 seperate amps like a power amp does (though some do), so you're effectively running a 2.67Ohm load. If the amp can handle 2 ohms, you're right but may have the volums descrepancy I mentioned earlier. If the amp can handle a 4 ohm min, you'll blow up the amp......