October 1, 2013 @ Wikipedia
The brown note is a hypothetical infrasonic frequency that would cause humans to lose control of their bowels due to resonance. Attempts to demonstrate the existence of a “brown note” using sound waves transmitted through air have failed.
The name is a metonym for the common color of human feces. Frequencies supposedly involved are between 5 and 9 Hz, which is below 20 Hz, the lower frequency limit of human hearing. High power sound waves below 20 Hz are felt in the body, not heard by the ear as sound.
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