Watching this year's Fourth of July fireworks display in Seattle, I wondered (not for the first time) how they coordinate the fireworks with the musical soundtrack--the hearts exploding right at the climax of "Unchained Melody," or the long fizzy streamers during the theremin part of "Good Vibrations," for instance. Not surprisingly, software's the answer.
The Seattle display was operated by a company called Pyro Spectaculars based out of Rialto, Calif., which reportedly uses a highly customized or home-built system to coordinate the music to the displays. But other pyrotechnicians might use combined hardware-software systems from FireOne or Infinity Vision.
FireOne's Web site gives some insight into the process of creating a display: the designer starts by creating an audio file composed of the songs that will be used in the display, then importing it into the software as a .wav file. Then, the designer selects from hundreds of shell types in FireOne's database, matching them up to specific points in the display--FireOne claims its software is accurate up to 0.01 of a second. The software puts a timecode on the music track, coordinates it with the electrical signals necessary to fire the shells, and outputs it as a file with the extension (of course) .fir. Of course, there's a manual option in case something goes wrong, as it did in Seattle's New Year's Eve celebration last year.
If you're interested in pursuing what sounds like one of the funnest jobs in the universe, you can find out more at the Pyrotechnics Guild International Web site.