From Muzzle to Microphone: Gunshot Audio Analysis

The analysis of sound as forensic evidence has traditionally received less attention than visual or physical data, yet every gunshot or cartridge case impact produces a unique acoustic fingerprint that can be objectively measured, visualized, and compared. This presentation introduces participants to the fundamentals of audio analysis within a forensic context — from the anatomy of a waveform to the interpretation of spectrograms and frequency spectra. Through step-by-step demonstrations using real recordings, we will explore how amplitude, frequency, and time domains reveal the dynamic structure of impulsive sounds such as gunfire and metallic impacts.

Building on this foundation, the session will present the results of recent experimental work involving controlled gunshot recordings and cartridge case drop tests. These case studies illustrate how sound signatures vary across firearm types, calibers, and environmental conditions, and how distinct resonance and decay patterns can assist in objective event comparison. Using tools such as Izotope and Audacity, attendees will see how quantitative frequency data can be combined with visual spectral analysis to support investigative and research efforts. By the end of the session, participants will have a clearer understanding of how audio evidence can complement traditional forensic reconstruction methods and open new avenues for identifying, classifying, and interpreting acoustic events in forensic science.