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YouTube Rewind 2018 is the single most disliked video on YouTube, receiving over 19 million dislikes since its upload on December 6, 2018. [1] This list of most-disliked YouTube videos contains the top 42 videos with the most dislikes of all time, as derived from the American video platform, YouTube's, charts. [2]
In contrast, humans are less averse to the white noise than to scraping. [4] A 1986 study used a tape-recording of a three-pronged garden tool similar to a fork being "grided" across a chalkboard, which roughly reproduces the sound of fingernails on chalkboard. The recording was then manipulated, removing pitches at the extremities and the median.
Hyperacusis is an increased sensitivity to sound and a low tolerance for environmental noise. Definitions of hyperacusis can vary significantly; it often revolves around damage to or dysfunction of the stapes bone, stapedius muscle or tensor tympani ().
To human ears, dog whistles only emit a quiet hissing sound. [6] The principal advantage of dog whistles is that they do not produce a loud, potentially irritating noise for humans that a normal whistle would produce and thus can be used to train or command animals without disturbing nearby people.
A cat can hear high-frequency sounds up to two octaves higher than a human. Not all sounds are normally audible to all animals. Each species has a range of normal hearing for both amplitude and frequency. Many animals use sound to communicate with each other, and hearing in these species is particularly important for survival and reproduction.
The ear's shape also allows the sound to be heard more accurately. Many breeds often have upright and curved ears, which direct and amplify sounds. As dogs hear higher frequency sounds than humans, they have a different acoustic perception of the world. [24] Sounds that seem loud to humans often emit high-frequency tones that can scare away dogs.
It is approximately the quietest sound a young human with undamaged hearing can detect at 1 kHz. [4] The threshold of hearing is frequency-dependent and it has been shown that the ear's sensitivity is best at frequencies between 2 kHz and 5 kHz, [5] where the threshold reaches as low as −9 dB SPL. [6] [7] [8]
The human ear can nominally hear sounds in the range 20 to 20 000 Hz. The upper limit tends to decrease with age; most adults are unable to hear above 16 000 Hz. The lowest frequency that has been identified as a musical tone is 12 Hz under ideal laboratory conditions. [6] Tones between 4 and 16 Hz can be perceived via the body's sense of touch.