Fireworks and SPL

[MacGeek]

I had an opportunity to enjoy the Bethel Park fireworks from a friends house last night and took some measurements just for grins and giggles.  I learned a few things I didn't expect:  Max SPL was 101 DB, and did not occur during the finale. Average SPL was 82DB.  The biggest booms occurred around 125 to 160 Hz.  Dynamic range was at least 50 DB and maybe as much as 60.

Of course these numbers are rough since I was trying to watch the show rather than the meter.  We were positioned 400 to 500 yards from the launch site.

Happy 4th to all.

[Sir Thrift-a-Lot]

Highly interesting.   I would only suggest that the 160 Hz represents the center of a very wide tone that likely gets as low as 15 Hz or so and as high as a few thousand.   I would also think that the higher frequencies are moving faster than the lower ones so that a recording of the blast would show a changing tone rather than a fixed one.   Very cool that you thought to do that.