May 2004, Brood X of the 17-year periodical cicada.
Brood X is sometimes called the 'Big Brood'
because it's the largest of the various cicada populations. The
17-year life cycle of the periodic cicada is the longest of any insect,
and the male cicada makes the loudest sound in the insect world.
In central New Jersey, you can drive for miles and not hear one,
then you find certain areas where the sound is incredible.
Here is a 20 second recording made in one such area, on Whiskey Lane in
Delaware Township, near Locktown, NJ.
I was on a 50 mile bike ride and didn't hear any until this 4 mile
stretch of road where it was really impressive,
and nearly constant.
(You can hear some traffic in the distance.)