Sounds Of Insects

"Recording Data on Insect Sounds: Wherever there is motion, some of the energy of the motion is liable to be transmuted to sound energy. Even though most of the insects are small, their motions can produce sounds. Some of the sounds are of such low amplitude that they remain inaudible to us without amplification; other sounds made by insects may be loud enough to become annoying. Wing beat tones, and other of the audible insect sounds were picked up directly by an Astatic 77 dynamic cardioid microphone. The internal sounds of the activity of insect flight muscles were picked up through a special probe affixed to RCA 5734 electro-mechanical transducer tube feeding into a specially built preamp. The most troublesome sounds to record proved to be those of insect footsteps. The specimens either clung to the protective mesh on the microphone, or they scampered or flew away too quickly to obtain a useable recording. Attempts were made with paper and with aluminum foil attached to a wire "needle" in a phono cartridge; further attempts were made with a specially built ribbon microphone, large enough for the insects to walk on the ribbon, but the results were poor. The footsteps recorded here were achieved by placing the specimens in a small cardboard box, whose bottom was replaced by a tightly stretched sheet of tissue paper. This was placed with the tissue paper only a fraction of an inch from the dynamic microphone. In effect this provided a double diaphragm of the microphone itself - and the results were not only loud and clear, but they sounded alike each time the same insect was permitted to walk. Many of the sounds included on this record were fed into specially designed preamplifier circuits, and thence to a 20-watt Williamson type amplifier. Output was fed to a VM model 711 tape recorder operating at 7 1/2 IPS, and recorded on Scotch brand 111 A 12 magnetic tape." Includes an 8-page insert with notes. Produced by Folkways Records, New York, © 1960