Signal convolution of recorded free-field gunshot sounds
Bruce E. Koenig, Shawn M. Hoffman, Hirotaka Nakasone, Steven D. Beck · Journal of the Audio Engineering Society · 1998
A field experiment was conducted using standard digital and analog recorders, telephone lines, a miniature radio-frequency transmitter-receiver system, and a video camcorder. Two pistols, two revolvers, and a shotgun were fired on an outdoor range three times each at distances of 3.05 m and 30.5 m, both toward the microphone-recorder test systems and from the side. The collected sound information was then evaluated using various methods. Excellent visual and statistical correlations were found only between the shots for the same weapon and recording device at each position. Almost all other combinations did not correlate closely with other recorded gunshot sounds. This research found specific microphones and tape recorders to respond uniquely to the high-level short-duration transients of live gunshot sounds, based on position, firing direction, and the weapon and ammunition type. Good overall correlation was found between visual and statistical comparisons of the waveforms over approximately the first 10 ms. Recommendations for further research and applications to forensic examinations are set forth.