Humans cannot hear sounds below 20 Hz or above 20,000 Hz because when sound waves travel too slowly or too quickly, our body can't translate that motion into signals our brains understand.
Especially dangerous is infrasound at the frequency of 7 Hz, since this sound, generating frequencies, close to characteristic frequencies of the organs of our body, may disturb the heart or brain activity.
Human ear perceives frequencies between 20 Hz (lowest pitch) to 20 kHz (highest pitch). All sounds below 20 Hz are qualified as infrasounds, althought some animals (ex. mole-rat, or elephant) are hearing them.
The commonly stated range of human hearing is 20 to 20,000 Hz. Under ideal laboratory conditions, humans can hear sound as low as 12 Hz and as high as 28 kHz, though the threshold increases sharply at 15 kHz in adults, corresponding to the last auditory channel of the cochlea.
Humans can detect sounds in a frequency range from about 20 Hz to 20 kHz. (Human infants can actually hear frequencies slightly higher than 20 kHz, but lose some high-frequency sensitivity as they mature; the upper limit in average adults is often closer to 15–17 kHz.)
In general, the fundamental frequency of the complex speech tone – also known as the pitch or f0 – lies in the range of 100-120 Hz for men, but variations outside this range can occur. The f0 for women is found approximately one octave higher. For children, f0 is around 300 Hz.
The human ear can hear frequencies up to 20kHz but we can't scream higher than 3kHz or so. The bottom end of our hearing range is 20Hz, which is still just below the deepest notes that most of us normally make (around 85Hz).
Measured in hertz (Hz), a healthy ear can hear a wide range of frequencies, from very low (20 Hz) to very high (20,000 Hz).
Conclusion: Auditory stimulation over a long time at a frequency of 5 Hz generates a coupling of brain activity that increases the capacity of immediate verbal memory.
Humans have a hearing threshold of around 0 decibels. Above this threshold, sounds with higher sound pressure levels are heard as louder noises. Sounds above 90 dB can lead to chronic hearing damage if people are exposed to them every day or all the time.
7 to 13 Hz.
This frequency is known as alpha waves. It may decrease anxiety, promote relaxation, and encourage positivity.
Therefore, a 6-Hz binaural beat on a 250 Hz carrier tone could be utilized as a stimulus for inducing a meditative state, as meditation has several advantages, such as stress reduction. However, achieving such effects via meditation require a deep meditative state that often takes a long period of time.
6 Hz beat enhances all area of the brain within 10 minutes. 8 Hz and 25 Hz beats have no clearly responses while 40 Hz beat enhances the responses in frontal lobe. These brain responses can be used for brain modulation application to induce the brain activity in further studies.
Beta waves are where we are the most alert. This helps us focus, concentrate, make decisions, and be analytical thinkers. These waves are fast with high frequencies between 10-15 hertz which are associated with anxiety.
After analyzing all the sounds the participants liked and hated, and placing them in order of unpleasantness, the researchers found that disagreeable sounds tend to be between the frequency range of about 2,000 to 5,000 Hz. Dr. Kumar said: “This is the frequency range where our ears are most sensitive.
More surprisingly, they found that the frequencies responsible for making a sound unpleasant were commonly found in human speech, which ranges from 150 to 7000 hertz (Hz). The offending frequencies were in the range of 2000 to 4000 Hz. Removing those made the sounds much easier to listen to.
Metaphorically speaking, 10 Hz is the natural idle speed of the brain's “engine” at rest, and lower speeds lead to “sputtering” in sensorimotor function (since sensorimotor stimuli cannot facilitate perceptual processing optimally at frequencies <10 Hz).
The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one hertz is the reciprocal of one second.
For example, musicians consider 20 to 80 hertz the low end of sound that people can often feel but not hear. Any sound above 10,000 hertz can be extremely uncomfortable to the human ear. Some people cannot hear at this range at all since the sounds are too high-pitched for the nerves in their ears to process.
Human hearing is sensitive to sounds from as low as 20 Hz to as high as 20,000 Hz in normal ears.
People of All ages without a hearing impairment should be able to hear the 8000hz. People under 50 should be able to hear the 12,000hz and people under 40, the 15,000hz. Under 30s should hear the 16,000hz, and the 17,000hz is receivable for those under 24.
For example, exposure to 4000 Hz produced damage in a restricted region of the cochlea and hearing loss for a relatively narrow range of frequencies; exposure to 125 Hz produced wide-spread inner ear damage and hearing loss throughout the frequency range 125 to 6000 Hz.
Vocal fry happens to occupy a frequency space between 75Hz and 100Hz, which is also 'deep voice territory' for men. So deep-voiced guys shouldn't be surprised if they match with Kim Kardashian more than Michael Jackson, who has a light voice with not much vocal fry.
The Frequencies We Can Hear
During a conversation, the fundamental frequency of a typical adult man ranges from 80 to 180 Hz and that of a typical adult woman from 165 to 255 Hz.