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what does "bridging" mean

Discussion in 'Amps and Cabs [BG]' started by schmittuml, Feb 20, 2005.


  1. schmittuml

    schmittuml Supporting Member

    Oct 25, 2004
    Lowell, MA
    ive heard talk of how you can get suh and such watts at 8ohms if you BRIDGE it.....what does bridging mean?
     
  2. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    in a stereo amp (either a head or a power amp) there are two seperate power amps. by selecting bridge mono mode (usually with a switch) both amps are connected together to provide power to one "load" you will also need to hook the speaker cable up a bit differently, this varies by amp.
    in that case each side of the amp "sees" 1/2 of the total impedance load. In the case of an amp that can power a minimum of 4 ohms per side, bridging into an 8 ohm load results in each side "seeing" a 4 ohm load. thus the power rating of the amp brige mono into 8 ohms is twice what it is rated for at 4 ohms per side. In the case of amps that are stable down to a mnimum of 2 ohms you can run them bridge mono into a 4 ohm load, which results in each side "seeing" a 2 ohm load and the amp putting out 2x what it is rated for at 2 ohms per side.