Discussion in 'Amps and Cabs [BG]' started by BoognishMang, Aug 21, 2001.

  1. BoognishMang

    BoognishMang Guest

    Aug 21, 2001
    Austin, Texas
    I got a Ampeg B-2R head: 200W@8 Ohms, 350W@4 Ohms.
    Hartke 4x10 cab: 400w

    Does this sound right...

    one cab connected to head = 200W output.
    two cabs connected to head = 350W output to each cab...?

    not sure how the whole ohms thing works.

  2. Luis Fabara

    Luis Fabara

    Aug 13, 2000
    Ecuador (South America)
    Audio Pro - Ecuador
    Ommage, or Impedance is a measure of resistance.

    For the higher resistance to the current flow, the amp will put lets watts.

    so.. at 8Ohms it will put 200 watts to whatever is connected..
    Could be 1, 2 ,4 x number of cabs as long as the Total impedance is 8Ohms.

    At 4 Ohms it will put 350 watts to whatever is connected.
    In parallel you should try to use cabinets with the same impedances.
    Say .. 2 Cabs of 8 Ohms each will produce a total Load of 4 Ohms.
    2 Cabinets of 4 Ohms will produce a load of 2 Ohms.
    But a 8 Ohm with a 4 Ohm will produce about 2.67 Ohm total load that would be nasty for an amp.

    So.. If you put 2 8Ohm cabs to that head, the head will push 350watts that will be distributed to the cabs connected.
  3. BoognishMang

    BoognishMang Guest

    Aug 21, 2001
    Austin, Texas
    forgot to add that cab is 8 ohms...
    so, to 8 ohm cabs give me 4 ohms
    and 350 w to EACH cab?
  4. No. 350/2 = 175Watts to each cab when running (2) 8 ohm cabinets.

  5. I could be wrong, but I know of no reason to think that an amp capable of handling a 2 ohm load would have any problem at all with a 2.67 ohm load.
  6. You're right. If the amp is rated for 2 ohms, then 2.67 is no problem for it. I think he was just saying don't parallel a 4 and an 8 into an amp rated for 4 ohms. Also, the power would be distributed uneven - 66% total power to the 4 ohm cab and 33% to the 8 ohm cab.

  7. BoognishMang

    BoognishMang Guest

    Aug 21, 2001
    Austin, Texas
    Ohmage was just a joke...thinking of Dubba's vocabulary.
  8. whitester

    whitester Guest

    ok just another q

    i've got a hartke 3500 amp with a 8 ohm 4x10

    so for one cab the amp use's 8 ohms

    and because there two jacks, if i hook up a second 8 ohm cab straight to the amp, it brings it down to 4ohms and increases the watage.

    So what if on one of the cabs i hooked up another 8 ohm cab (in series i think its called.)
    what happens then.

    from previous post, i get that hooking a 4 and 8 ohm cabs into one amp would be bad, (if amp rated wrong.) But say if you added another that was 16 ohms. would this then balance out the ohms.

    but i guess then power wouldn't be evenly distributed.

    oh well, i just wish i had the cash to get three 4x10 cabs

  9. Luis Fabara

    Luis Fabara

    Aug 13, 2000
    Ecuador (South America)
    Audio Pro - Ecuador
    Im sorry, my mistake.
    What I was trying to say is that a 8ohm and 4 ohm cabinet dont make 6 Ohms.
    and I was thinking about the Ampeg that handles a minimum load of 4 Ohms.

    I stand corrected.
  11. neptoon


    Jul 25, 2000
    Kings Bay, GA
    ohmage, indeed...