The most powerful pipes in a cathedral organ are the 32-foot stops. These massive pipes produce a frequency of roughly 16 Hz. This frequency is technically infrasonic, meaning it is below the normal range of human hearing. Instead of 'hearing' a note, the listener feels a physical vibration in their chest and the floor. This effect was often used in religious settings to create a sense of 'awe' or divine presence. To produce this sound, the pipe must be nearly 32 feet long, requiring immense air pressure provided by large bellows.