The physics of sound is often studied in introductory physics class experiments involving a tube of resonating air. In typical setups, pistons control the length of a cylindrical space or a microphone is moved within a tube.1 While these activities are useful and can be made very quantitative, they don't directly demonstrate the sounds that are most familiar to students, such as human voices and musical instruments. Fortunately, several sound spectrum analysis programs are available that can bridge this gap.2