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How much wattage is there really?

Discussion in 'Amps and Cabs [BG]' started by Ralphdaddy, Nov 20, 2003.


  1. Ralphdaddy

    Ralphdaddy Supporting Member

    Nov 6, 2003
    Chicago, Illinois
    Ok, here's my problem. I've got an Ashdown MAG410T cabinet rated at 350@8 ohms and a GK 400rb-IV head rated at 280 watts @4 ohms and 180 watts @8 ohms. Does this mean my cabinet will only be getting 180 watts from the head??? I'm totally clueless here, please explain this whole situation to me. Thanks in advance.

    Ralph
     
  2. JMX

    JMX Vorsprung durch Technik

    Sep 4, 2000
    Cologne, Germany
    The calculated output power is around 180W, but in real life it will be below that depending on your bass signal, with maybe some single peaks in that 180W area or even above that (power amp "distortion").
     
  3. nonsqtr

    nonsqtr The emperor has no clothes!

    Aug 29, 2003
    Burbank CA USA
    Hi Ralphdaddy, the power you'll get is what is being delivered by the amp. So if your amp is rated 180 watts at 8 ohms, that's what you'll get. GK's are pretty good for delivering the rated power. Note that there are many different ways for measuring the power that is being delivered. The common denominator is the "RMS Power", which is defined as the power that produces the equivalent heat dissipation in a resistor (equivalent to DC, which is much easier to measure, according to Ohm's Law). I think GK's are rated in RMS watts. 180 watts is nice and loud, that should get you through rehearsals and "most" gigs. More may be needed outdoors.

    To get more power out of your amp, you'll need to take the load impedance down to 4 ohms. Basically this means putting another 8 ohm cab in parallel with the one you've already got. Under no circumstances go below the minimum rated load impedance of the amp.