Ultrasound's minimum barrier is about 20 kHz. Interestingly, "[c]arefully-designed scientific studies have been performed supporting what the authors call the hypersonic effect - that even without consciously hearing it, high-frequency sound can have a measurable effect on the mind."
"It is a fact in psychoacoustics that children can hear some high-pitched sounds that older adults cannot hear, because in humans the upper limit pitch of hearing tends to become lower with age."
"Some animals – such as dogs, cats, dolphins, bats, and mice – have an upper frequency limit that is greater than that of the human ear and thus can hear ultrasound."
As for infrasound: The upper bound seems to be 20 Hz. That means generally, humans can hear anything between 20 Hz and 20,000 Hz.
"[A]nimals have been known to perceive the infrasonic waves carried through the earth from such natural disasters and can use these as an early warning. ... It is not known for sure if this is the exact reason, as some have suggested that it was the influence of electromagnetic waves, and not of infrasonic waves, that prompted these animals to flee. Elephants have been known to hear infrasound from two and a half miles away."
"Infrasound has been known to cause feelings of awe or fear in humans. Since it is not consciously perceived, it can make people feel vaguely that supernatural events are taking place."
Unless it's like Taiga says and they found a frequency that only the Clovers and crabs can hear.
no subject
Ultrasound's minimum barrier is about 20 kHz. Interestingly, "[c]arefully-designed scientific studies have been performed supporting what the authors call the hypersonic effect - that even without consciously hearing it, high-frequency sound can have a measurable effect on the mind."
"It is a fact in psychoacoustics that children can hear some high-pitched sounds that older adults cannot hear, because in humans the upper limit pitch of hearing tends to become lower with age."
"Some animals – such as dogs, cats, dolphins, bats, and mice – have an upper frequency limit that is greater than that of the human ear and thus can hear ultrasound."
As for infrasound: The upper bound seems to be 20 Hz. That means generally, humans can hear anything between 20 Hz and 20,000 Hz.
"[A]nimals have been known to perceive the infrasonic waves carried through the earth from such natural disasters and can use these as an early warning. ... It is not known for sure if this is the exact reason, as some have suggested that it was the influence of electromagnetic waves, and not of infrasonic waves, that prompted these animals to flee. Elephants have been known to hear infrasound from two and a half miles away."
"Infrasound has been known to cause feelings of awe or fear in humans. Since it is not consciously perceived, it can make people feel vaguely that supernatural events are taking place."
Unless it's like Taiga says and they found a frequency that only the Clovers and crabs can hear.