Blueprint 1803 spl

Discussion in 'Archived Threads 2001-2004' started by Jerry Parker, Nov 3, 2001.

  1. Jerry Parker

    Jerry Parker Stunt Coordinator

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    Well i brought out the trusty old radio shack spl meter to do some testing on my 1803. I played a song with bass beats in the 30hz region, and the meter was hitting about 118dB, or corrected at about 120dB!!! And this was with *only* 250 watts of power. This thing is truely a monster. I cant wait until I get a PA amplifier capable of over 1kW. That will be fun to watch the walls move!
    Also, I am able to get the driver to excur about 1.5 inches with only 250 watts of power. The output at this level is obviously distorted, but can I actually harm the driver by doing this? And, when playing at higher volumes, when higher frequencies are played, the subwoofer sounds REALLY bad. Does this have to do with the high inductance VC? Thanks.
     
  2. Rick Chwiendacz

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    If the output is highly distorted at that level, then it's highly likely you've driven your amplififier far into clipping. You're probably giving your sub closer to 300-350W RMS, and if there's audible nasty distortion, you're likely feeing your sub what amount to square waves.
    And no, I highly doubt you can harm that driver even if you push that 250W amp as far into clipping as it can go. Whether or not the amp will survive is another story. Some amps do not like to be clipped.
    About the high frequencies - the cone breakup modes of this 18" driver are likely to be quite low in frequency, and the high inductance of the voice coil isn't going to help matters. This driver really should be crossed no higher than 80hz with a 4th order lowpass, and ideally closer to 60hz.
    - Rick
     

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