Which Generator for small PA setup?

Discussion in 'Professional Fireworks' started by Dodgey, Feb 22, 2018.

  1. 8E3F9310-B02D-4E1C-8D14-D201901B1CE9.jpeg
    Surprisingly this little Jenny is running that whole stack. The system had two stacks each with one of these little honda’s not sure what amps but title claimed it was a 20k rig (image taken from you tube vid)
     
  2. Pyro Ed

    Pyro Ed Pro Firer/Crew

    Deffo not a 20K rig. Those are EU2000i generators. My bass amp alone would wipe that out.
     
    DannyB likes this.
  3. Pyro Ed

    Pyro Ed Pro Firer/Crew

    But how was it loaded? I used to run with a 5K AVR regulated diesel genset, and that would struggle on some bass heavy tracks (voltage would sag) My amps at the time were mono bridged at 2200w RMS into 4 ohms and so would draw on average around 6-7 amps limited just before clipping (they were run hard), although its all completely changed since then.
     
  4. Arthur

    Arthur Pro Firer/Crew

    As a first approximation, an amplifier usually draws from the mains 25% of it's rated audio power. Small generators usually don't do music well if the bass power starts to interfere with the rate that the AVC or regulation works (or doesn't). Some resistive load (5 - 10%) usually helps.
     
  5. Pyro Ed

    Pyro Ed Pro Firer/Crew

    Way way way to over-simplistic.
     
    Pyro Pete likes this.
  6. Pauld201

    Pauld201 Pro Firer/Crew

    I’d love to know what sort of power generators you’d need for this lot. :)

    C870A983-1587-46E0-9F23-D3E7FB5DE98B.jpeg
     
    Pyro Ed likes this.
  7. Pyro Ed

    Pyro Ed Pro Firer/Crew

    If I remember rightly Glastonbury uses 4x 500Kw sync sets. Lighting is the biggest draw, especially things like the Marin Atomic 3000 strobes. They cause such a surge that the generators (in containers) literally jump.
     
    Pauld201 and Jon like this.
  8. Jon

    Jon Pro Firer/Crew

    They are pretty versatile strobes though! :p Programmed them as lightning effects, blinding effects, singular pulse for a gun shot....they are awesome strobes in theatre let alone live gigs.
     
  9. Pyro Ed

    Pyro Ed Pro Firer/Crew

    That they are, but get a load of them and the power requirements make your eyes water!
     
    Jon likes this.
  10. elmo

    elmo Pro Firer/Crew

    Why is it that sometimes you can hear a slight generator noise through the speakers and how can you stop it?
     
  11. Is the generator left free standing or do you use an earthing rod whacked good n deep in the ground
     
  12. elmo

    elmo Pro Firer/Crew

    Free standing?
     
  13. I was told an earthing rod can solve the issue or if using phono type connectors try looping a piece of wire around the outside circular part and connecting other end to gnd on mixer. All second hand info and unsure if it works. Cars with ‘da big boom system’ can suffer a rumbling Brrrrrrrrrr noise coming through the subs and the phono - wire - gnd method works to stop it. I believe it’s called ignition interference again second hand info I’ve picked up so don’t shoot the messenger:rolleyes:
     
    elmo likes this.
  14. If your playing via a laptop make sure the adapter doesnt have an earth wire.. just live and neutral.

    Removes the ground loop interference.
     
  15. elmo

    elmo Pro Firer/Crew

    No laptop
    Was cobra firing system so audio box plugged straight into active speakers via phono to xlr cables
     
  16. EventTech

    EventTech Pro Firer/Crew Supports UKFR

    This could possibly be down to signal levels with high signal levels from the audio box. Have you tried lowering the audio box output and increasing the amplifier itself to see if that makes any difference?
    One option could be to try connecting each of the audio outs to a DI box using an phono to 1/4" jack cable and then run balanced XLR to the speakers. I prefer active DI boxes which require either phantom power from the sound desk (or a 9v battery) whereas passive DI boxes do not require a battery supply.
    My personally choice would be to connect the audio box via a sound desk as you have better controls of input and output signals.
     
    elmo likes this.
  17. Pyro Ed

    Pyro Ed Pro Firer/Crew

    First question before anything else. Does the amplifier produce this whilst ON but no input connected into it?
     
  18. B45A4269-3CF0-4A95-B288-1739B522938F.jpeg Behringher do a hum destroyer DI box for about £25
     
  19. Pyro Ed

    Pyro Ed Pro Firer/Crew

    Need to establish where the noise is coming from first, also what type of generator is it.
     
  20. elmo

    elmo Pro Firer/Crew

    Bog standard Honda generator