Ohm Confusion!

Discussion in 'Amps and Cabs [BG]' started by metalloid, Feb 4, 2001.

  1. metalloid

    metalloid Supporting Member

    Feb 2, 2001
    I have been plaing guitar and drums for a long while now, but now that I am becoming more active in playing bass, I need to know more about Ohms.

    I understand a small amount of info, but can someone help me out?



    (sorry for the stupid question in advance)
  2. CS


    Dec 11, 1999
    Hey Joe

    Thats a broad question so a broad answer plus some guesses as to why you asked.[​IMG]

    Ohms is a measure of resistance.

    A solid state amplifier will dish out say 200w into 4 ohms but only approx 140w into 8 ohms. Naughty amp makers will say an amp is 200w but forgeting to tell you that you need another cabinet. Valve amps will have a rocker switch or old ones will have a two prong pin to select impedance.

    So our combo is running at 8 ohms until you plug in an 8 ohm extension. however hook up a 4 ohm cab instead and its running below 4 ohm which could wreck the amp.

    So before you decide to buy or hook up amps and cabs ask, its cheaper. [​IMG] (I love these smily's)

  3. virtual.ray


    Oct 25, 2000
    Yeah,they really are naughty,those amp makers.
  4. Ok, for the demonstration, you have a 300w head.

    Into a 4 Ohms cabinet, you will use 300w.

    Into an 8 Ohms cabinet, you will only use 170w, because the electrical resistance is greater. So less watts will pass into it.

    If you hook up 2 8 Ohms cabinets, you will have a the equivelent (from the heads point of view) of a 4 Ohms cabinet, because something happens in the head. So when you hook up 2 8 Ohms, you will use your full 300w.

    I hope I'm right.