Note: above 300 GHz, the absorption of electromagnetic radiation by Earth's atmosphere is so great that the atmosphere is effectively opaque to higher frequencies of electromagnetic radiation, until the atmosphere becomes transparent again in the so-called infrared and optical window frequency ranges.
The ELF, SLF, ULF, and VLF bands overlap the AF (audio frequency) spectrum, which is approximately 20–20,000 Hz. However, sounds move at the speed of sound, rather than the speed of light.
Electrical connectors designed to work at radio frequencies are known as RF connectors. RF is also the name of a standard audio/video connector, also called BNC (BayoNet Connector).
