subloud
Subloud is a term that refers to the sounds or frequencies that are below the range of human hearing. The human ear is capable of detecting sounds within a specific frequency range, typically between 20 Hz and 20,000 Hz. Frequencies below this range are considered subloud. These sounds are often associated with various natural phenomena and technological devices. For instance, infrasound, which is below 20 Hz, can be generated by large-scale events such as volcanic eruptions, earthquakes, and meteor impacts. It can also be produced by man-made sources like large industrial machinery and supersonic aircraft. Infrasound can sometimes be felt as a low-frequency vibration rather than heard. Ultrasound, on the other hand, refers to frequencies above 20,000 Hz and is used in medical imaging and various industrial applications. The study of subloud frequencies is an emerging field, with potential applications in geophysics, seismology, and even in the detection of underground structures.