Cicadas probably come to mind as a well-known noise maker. The males can produce sound, sometimes up to 120 decibels - technically loud enough to cause hearing loss in humans! They have a thin membrane on the outer abdominal wall, called a tymbal. As the abdominal muscles contract and relax, it causes the tymbal to click. Cicadas rapidly vibrate the membrane and the sound amplifies in enlarged air chambers in the abdomen. Each species would have it's own "song" to attract females.
Periodical cicada, www.ipmimages.org.
Field crickets use their wings to create sound. Photo by David Cappaert, Michigan State University, www.ipmimages.org.
Other insects, like grasshoppers and beetles, scrape their legs to make sound. Grasshoppers have stiff peg-like spines on the hind legs that they rub against their wings. Some long-horned grasshoppers will rub their front legs together for their species-specific "songs."
Striped slant-face grasshopper with stiff spines on the hind leg used for stridulation. Photo by Gerry Fauske, North Dakota State University.
Some insects use their heads or even their mouthparts to make clicking noises. But perhaps the weirdest noise-making insect I discovered was the tiny water boatman. This aquatic insect can "sing" at 99 decibels by rubbing its penis against his abdomen. Don't ask me how scientists thought of researching this idea or how they collected the data.
The tiny water boatman can generate a very loud sound, www.bbc.co.uk.
I found a few nice websites that have audio clips of insects making noise. Enjoy!
Insect Sounds, www.naturesongs.com/insects.html
Bug Bytes, www.ars.usda.gov/sp2userfiles/person/3559/soundlibrary.html
Songs of Insects, www.musicofnature.org/songsofinsects/index.html