| |||
| infrasonic sounds | |||
| infrasound Vibrations of the air at frequencies too low to be perceived as sound by the human ear, below about 15 hertz | |||
| infrasound | |||
| |||
| infrasonic sounds | |||
| infrasound Vibrations of the air at frequencies too low to be perceived as sound by the human ear, below about 15 hertz | |||
| infrasound | |||
