Keyword:
Infrasound

Infrasound refers to sound whose frequency is below approximately 16–20 Hz, i.e., below the human hearing threshold. The human ear is virtually insensitive to infrasound. Infrasound is a ubiquitous, general component of the natural environment, but it is also generated artificially, for example, in transportation or by technical devices. Some animals, such as elephants, giraffes, and blue whales (infrasound waves have a particularly long range in water), can perceive sound in part of this frequency spectrum and probably also use these sounds for communication. Infrasound waves of very low frequency in particular propagate well over long distances. The hearing range of the human ear in young people extends from about 16 hertz to a maximum of 20,000 hertz. In acoustics/room acoustics, the range between 125 Hz and 4 kHz (octave bands) plays an important role.