Infrasound

The larger church organs use infrasound, which people do not hear, but feel as vibrations in their bodies.

Scientists think that giraffes use infrasound to communicate over long distances.

Research by Jon Hagstrum suggests that homing pigeons use low-frequency infrasound to find their way home.

At the other end of the spectrum are very low-frequency sounds (below 20 Hz), known as infrasound.

Elcor speech is ponderous and monotone. Among themselves, scent, slight movements, and subvocalized infrasound convey shades of meaning that make a human smile seem as subtle as a fireworks display. Since their subtlety can lead to misunderstandings with other species, the elcor often go out of their way to clarify when they are being sarcastic, amused, or angry.