Generator size for PA on flatbed truck?

Discussion in 'Live Sound [BG]' started by BartmanPDX, Jun 24, 2020.

  1. My band might be playing a gig on the back of a flatbed truck for a slow parade of bands through a town.

    They are asking how big of a generator we need for the band.

    We don't use monitors (everything through the PA) but we would be using a pair of QSC K10s and a sub (KW181 or my small PA sub). There would also be the mixer/inear monitor system though I don't think that would draw too much power.

    How big of a generator would we need for the truck? I'm totally at a loss. I've played on a flatbed before but it was never moving and I've never had a generator for our PA.

    Many thanks for any help you can give me.
  2. Gordo350


    Sep 20, 2018
    Look on the back of the amp and see what the rated wattage is. My PA says 650 watts at 50 Hertz. I run it of a 2200 watt generator
    Just make sure it's a pure sine wave generator so it provides clean power
    BartmanPDX likes this.
  3. Wasnex


    Dec 25, 2011
    Add up the total power required by all equipment and then ask for a little bit more IMHO.

    Another thing to check: Some generators have an Eco mode that let's the generator run more fuel efficiently. When demand is low, the engine idles down. When more power is required, the RPM goes up to meet demand. This is not effectively for music because the generator cannot anticipate the power demands of the music. So when the band is playing loud music, the Eco mode should be turned off. I.E. The generator should be running at full potential, rather than trying to track the constantly changing power demands of live music.
    BartmanPDX likes this.
  4. Well, crap.

    Turns out my drummer has vertigo/balance issues and can't play on a moving truck no matter how slow it's going. So we aren't playing the gig. :(

    It's too bad. I was pretty excited to finally have a gig on the books again.
  5. DirtDog


    Jun 7, 2002
    The Deep North
    Well that sucks for you guys!

    For future reference (when not playing on a float), you also need to consider the total amount of current required in your circuit. Add up all the amperage for your gear and find a generator that can generate that current. Eg, the Honda generator that we’ve used is 1800W and 15A. That’s powered two PA speakers, small guitar amps, pedals etc.
    BartmanPDX likes this.
  6. BLDavis

    BLDavis May the Tort be with you.

    May 21, 2009
    Ellenboro, NC
    This, and make sure you have a way to anchor or strap down EVERYTHING on stage. Mic stands, amps guitar stands, drums ect..........Ask me how I learned this. :eek:
    btmpancake likes this.
  7. 4Mal

    4Mal Gold Supporting Member

    Jun 2, 2002
    Columbia River Gorge
    15 amps = 5 K series boxes at full power. The magic of the QSC power supply...

    In practical terms, had that gig gone on a Honda EU-3000i or the Subaru or Yamaha equivalents are what I would have spec'ed. Those aren't quite as quiet as the eu-2000i but not terrible. I would also have positioned the gennie on a rear corner, tied down of course and used some 2x4 and ply to baffle the noise out and away from any live mics.

    Bart- you can always borrow my Alesis SR-18 ;-)
    Last edited: Jul 1, 2020
  8. What does he think you are are paying him for?! Have him run along behind playing side snare.