Ear potential that is transmitted along the spiral ganglion, which sends information through the auditory portion of the vestibulocochlear nerve to the temporal lobe of the brain. The human ear can generally hear sounds with frequencies between 20 Hz and 20 kHz (the audio range). Sounds outside this range are considered infrasound (below 20 Hz) or ultrasound (above 20 kHz) Although hearing requires an intact and functioning auditory portion of the central nervous system as well as a working ear, human deafness (extreme insensitivity to sound) most commonly occurs because of abnormalities of the inner ear, rather than in the nerves
North American Regional Broadcasting Agreement and "Clear Channel" frequencies. The only provision the FRC made addressing international concerns was that six frequencies — 690, 730, 840, 910, 960, and 1030 — were designated for exclusive Canadian use. On May 5, 1932, through an exchange of letters, the U.S. and Canada informally endorsed and expanded the 1928 standards, including recognition of Canadian use of 540 kHz. During the 1930s, Canada also began using 1510 kHz, while in 1934 the U.S. authorized two experimental high-fidelity stations on each of 1530 and 1550 kHz. By 1939, Cuban stations existed on frequencies as high as 1600 kHz. As other