SPL Shootout...

I was waiting at a red light yesterday when a guy in an SUV pulled along side of me. The music coming out of his vehicle was so loud, it was making my car thump. I didn't know the (hip-hop) song, but I could clearly hear the lyrics from inside my car with the windows rolled up and the a/c on high.
A friend of a friend owned a car stereo shop who did custom work. By word of mouth, people came from miles for him to install some HUGE systems. Most upgraded car sound systems have special speakers and a sub bass box in the trunk that only plays the low notes.
Some background:
It's usually stated the range of human hearing is 20 to 20,000 HZ (hertz or cycles per second) and there are many factors that affect those numbers. loud sounds for example. Industrial workers in high noise environments are required to use hearing protection. The guys at airports who direct jets into the gate wear noise reducing protection. Loud sounds without hearing protection will accentuate hearing loss. Ask any Heavy Metal musician if he's got hearing loss and their first response could be "Huh?"

SPL is the acronym for Sound Pressure Level and there are metering devices for measuring pressure. I've always heard sound pressure is measured in decibels for music loudness and for the purpose of this blog, any pressure musical or not, is considered the same. Sub-octave sounds below the threshold of human hearing are felt more than actually heard and can be described as pulsating air.

So what's the purpose of a 5,000 watt sound system in your SUV?
It doesn't follow logic, but in certain circles there is status for having 'more bass' much the same as someone on a Saturday night doing racing with the fastest car or the most horsepower.

The shootout is a competition event where vehicles are 100 yards (or more) from the judge who has a decibel meter. They play their best sound with hope of generating more SPL's at the greatest distance.



This style of competitive volume isn't limited to the United States, as many of the photos I've seen are from enthusiasts in European countries.

Because of the high power current draw, the vehicles have to be equipped with several alternators and batteries to generate sufficient wattage.