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What happens if I plug a 4ohm head ina 8ohm cabinet???

Discussion in 'Amps and Cabs [BG]' started by vene-nemesis, Jan 15, 2005.


  1. Joe Beets

    Joe Beets Guest

    Nov 21, 2004
    It won't be loud enough and you will wish you had another 8 ohm cabinet.
     
  2. DubDubs

    DubDubs

    Aug 23, 2004
    Los Angeles
    If it's Solid State (which it probably is) the 4ohm rating is just the MINIMUM rating so 8ohms is fine you just won't get as much power out of it but it's not necessarily going to be too quiet either and you'll have an advantage over having 1 4ohm cab becasue you can always add another 8ohm cab later. Bottom like you'll be fine.
     
  3. Razor

    Razor

    Sep 22, 2002
    Dallas
    That pretty much sums it up...

    Get another 8 Ohm cab to hook to the one you already have...that way the amp "sees" a 4 Ohm load...thereby putting out more power.
     
  4. vene-nemesis

    vene-nemesis Banned

    Jul 17, 2003
    Bilbao España

    I've minimal knowledge in electricity, so i would have to hook another 8ohm cab in parallel with the first so i get the inverse of 1/8ohm + 1/8ohm = 2/8ohm = 1/4ohm resulting in 4ohm impedance isnt it?????
     
  5. vene-nemesis

    vene-nemesis Banned

    Jul 17, 2003
    Bilbao España

    i think it is solid state, is a carlsbro poweramp with an ampworks hooked to it (soon to be changed for a Sansamp RBI)
     
  6. IvanMike

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

    Nov 10, 2002
    Middletown CT, USA
    for a minimal knowledge you pretty much have all the knowledge you need to use amps. :D
    FYI, except in very rare cases all amps have their speaker outputs wired in parallel. likewise, cabinets that have more than one input have them wired in parallel as well so when you "daisy chain" them together you get parallel wiring.
     
  7. vene-nemesis

    vene-nemesis Banned

    Jul 17, 2003
    Bilbao España
    ok here i need your help a little more, im buying a 600W @ 8ohm cabinet to run with a 4ohm 400W@ 4ohm per side bass head, ive read the ohm FAQ this morning but couldnt understand what exactly happens when pepple does this kind of thing??? does it ends up in 268W @ 8ohm of power output out of my Power amp?
     
  8. IvanMike

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

    Nov 10, 2002
    Middletown CT, USA
    well tell us what the head is
    1st, if you run the cab off of one side you'll have to check with the manufacturer of the head how many watts each side will put out at 8 ohms. If they say it puts out 268 watts into 8 ohms per side then running that 8 ohm cabinet off of one side will result in 268 watts gong into it. the fact that its a 600 watt cab doesnt matter. all that means is it can handle 600 watts.
    hopefully the head you are talking about can be run in bridge mono mode. then you can run both sides into that one cabinet (you do this with one cord, check with the amp's manual about how to hook it up and you'll have to switch it to bridge mono mode). then that cab will get 800 watts. when you run an amp in bridge mono mode each side "sees" 1/4 of the total impedance load so they'll operate at 4 ohms and put out 400 watts each. It's fine to run a 600 watt cab with 800 watts, you just have to be careful not to overdrive it - (you'll hear it).