What is the highest pitch audible to humans?
Harman Kardon
In 1959, Harman Kardon marketed the Citation II, an early ultra wideband stereophonic tube amplifier. Designed by Stewart Hegeman, it featured 60 watts/channel output with a frequency response of 18-60,000 Hz at 20 watt output. The company promoted their philosophy of designing high fidelity sound using amplifiers that provided widest possible audio bandwidth. Although the human ear highest audible range is around 20,000 Hz, the full range of sound goes beyond that with harmonics and overtones that may be beyond the hearing range of the human ear. These harmonics interact with other frequencies to produce audible secondary sounds or interference. Harman Kardon promoted the design in audio magazines and product brochures.
Outer ear
One consequence of the configuration of the outer ear is selectively to boost the sound pressure 30- to 100-fold for frequencies around 3 kHz. This amplification makes humans most sensitive to frequencies in this range — and also explains why they are particularly prone to acoustical injury and hearing loss near this frequency. Most human speech sounds are also distributed in the bandwidth around 3 kHz.
Hearing range
Mice have large ears in comparison to their bodies. They hear higher frequencies than humans; their frequency range is 1 kHz to 70 kHz. They do not hear the lower frequencies that humans can; they communicate using high frequency noises some of which are inaudible by humans. The distress call of a young mouse can be produced at 40 kHz. The mice use their ability to produce sounds out of predators' frequency ranges to alert other mice of danger without exposing themselves, though notably, cats' hearing range encompasses the mouse's entire vocal range. The squeaks that humans can hear are lower in frequency and are used by the mouse to make longer distance calls, as low frequency sounds can travel farther than high frequency sounds.
Whistle register
Many babies and small children regardless of sex can produce sounds in the frequency range of the whistle register without any conscious effort. Typically, the whistle register in children extends from the soprano "high C" (C or 1046.5 Hz) to two Gs above (G or 3136 Hz). Some children, however, can produce pitches that surpass the upper limit of the keyboard.
Whistle register
The whistle register (also called the flute register or whistle tone) is the highest register of the human voice, lying above the modal register and falsetto register. This register has a specific physiological production that is different from the other registers, and is so called because the timbre of the notes that are produced from this register is similar to that of a whistle.
Black snub-nosed monkey
The Black snub-nosed monkey lives at the highest altitude of any known non-human primate. The highest recorded altitude of a group of this species is 4700 m. Surviving in such extreme conditions is only made possible by a mutation in the primate's genomic DNA sequence that allows increased resistance to oxygen deprivation (hypoxia). Other mutations in the DNA sequence have been found to be harmful to the monkeys, as there is evidence of inbreeding and low genetic diversity among populations.
Sound pressure
Ears detect changes in sound pressure. Human hearing does not have a flat spectral sensitivity (frequency response) relative to frequency versus amplitude. Humans do not perceive low- and high-frequency sounds as well as they perceive sounds between 3,000 and 4,000 Hz, as shown in the equal-loudness contour. Because the frequency response of human hearing changes with amplitude, three weightings have been established for measuring sound pressure: A, B and C. A-weighting applies to sound pressures levels up to , B-weighting applies to sound pressures levels between and , and C-weighting is for measuring sound pressure levels above .
WCAT Radio Tower
The WCAT Radio Tower, at , is the tallest man-made structure in Vermont. It is located in Burlington, Vermont. It broadcasts at 5000 Watts. WCAT is the only radio station that has a radio tower within the city limits of Burlington. There is a second tower, also built in 1981, which is a directional aerial beside the WKDR Radio Tower. There is also a third tower on the site, which is tall.
Bioacoustics
Sounds used by animals that fall within the scope of bioacoustics include a wide range of frequencies and media, and are often not ""sound"" in the narrow sense of the word (i.e. compression waves that propagate through air and are detectable by the human ear). Katydid crickets, for example, communicate by sounds with frequencies higher than 100 kHz, far into the ultrasound range. Lower, but still in ultrasound, are sounds used by bats for echolocation. On the other side of the frequency spectrum are low frequency-vibrations, often not detected by hearing organs, but with other, less specialized sense organs. The examples include ground vibrations produced by elephants whose principal frequency component is around 15 Hz, and low- to medium-frequency substrate-borne vibrations used by most insect orders. Many animal sounds, however, do fall within the frequency range detectable by a human ear, between 20 and 20,000 Hz. Mechanisms for sound production and detection are just as diverse as the signals themselves.
Just-noticeable difference
The "just-noticeable difference (JND)" (the threshold at which a change is perceived) depends on the tone's frequency content. Below 500 Hz, the JND is about 3 Hz for sine waves, and 1 Hz for complex tones; above 1000 Hz, the JND for sine waves is about 0.6% (about 10 cents).
The JND is typically tested by playing two tones in quick succession with the listener asked if there was a difference in their pitches. The JND becomes smaller if the two tones are played simultaneously as the listener is then able to discern beat frequencies. The total number of perceptible pitch steps in the range of human hearing is about 1,400; the total number of notes in the equal-tempered scale, from 16 to 16,000 Hz, is 120.
Middle ear
The middle ear efficiency peaks at a frequency of around 1 kHz. The combined transfer function of the outer ear and middle ear gives humans a peak sensitivity to frequencies between 1 kHz and 3 kHz.
Radio Gaúcha AM Guaíba Mast
The Radio Gaúcha AM Guaíba Mast (also known as IPÊ Mast or as Antena do Parque Técnico Maurício Sirotsky Sobrinho) is the tallest man-made object in Brazil. The Radio Gaúcha AM Guaíba Mast is used by Radio Gaúcha for medium-wave broadcasting on 600 kHz with 100 kW. The mast is located in the city of Guaíba, in the metropolitan area of Porto Alegre, state of Rio Grande do Sul, at . It is a 230-metre (755 ft.) tall, ground-insulated guyed mast radiator, and a nearly perfect replica of Warsaw Radio Mast. The Radio Gaúcha AM Guaíba Mast was built in 1985/1986 to improve the transmissions of football matches.
Cat senses
Humans and cats have a similar range of hearing on the low end of the scale, but cats can hear much higher-pitched sounds, up to 64 kHz, which is 1.6 octaves above the range of a human, and even 1 octave above the range of a dog. When listening for something, a cat's ears will swivel in that direction; a cat's ear flaps (pinnae) can independently point backwards as well as forwards and sideways to pinpoint the source of the sound. Cats can judge within the location of a sound being made away—this can be useful for locating their prey.
Stimulus modality
The human ear is able to detect differences in pitch through the movement of auditory hair cells found on the basilar membrane. High frequency sounds will stimulate the auditory hair cells at the base of the basilar membrane while medium frequency sounds cause vibrations of auditory hair cells located at the middle of the basilar membrane. For frequencies that are lower than 200 Hz, the tip of the basilar membrane vibrates in sync with the sound waves. In turn, neurons are fired at the same rate as the vibrations. The brain is able to measure the vibrations and is then aware of any low frequency pitches.
Audiogram
For humans, normal hearing is between −10 dB(HL) and 15 dB(HL), although 0 dB from 250 Hz to 8 kHz is deemed to be 'average' normal hearing.
Rotary woofer
In the early 1970s, researchers noted that while humans could detect frequencies below 20 Hz, the ear was much less sensitive to these frequencies. As a result, increased sound pressure levels are required to perceive these sounds. These frequencies are often not audible but still subliminally detected by humans (see: Infrasound). Typical subwoofers using moving cones do not transmit energy very well to the air below 20 Hz, and thus their sound pressure level (SPL) falls off significantly below this frequency.
Hearing loss
Human hearing extends in frequency from 20–20,000 Hz, and in intensity from 0 dB to 120 dB HL or more. 0 dB does not represent absence of sound, but rather the softest sound an average unimpaired human ear can hear; some people can hear down to −5 or even −10 dB. Sound is generally uncomfortably loud above 90 dB and 115 dB represents the threshold of pain. The ear does not hear all frequencies equally well; hearing sensitivity peaks around 3000 Hz. There are many qualities of human hearing besides frequency range and intensity that cannot easily be measured quantitatively. But for many practical purposes, normal hearing is defined by a frequency versus intensity graph, or audiogram, charting sensitivity thresholds of hearing at defined frequencies. Because of the cumulative impact of age and exposure to noise and other acoustic insults, 'typical' hearing may not be normal.Hearing loss is sensory, but may have accompanying symptoms:
Graeme Clark (doctor)
After successfully completing the surgery in 1978, with his post-doctoral colleague, Yit Chow Tong, Clark discovered how multi-channel electrical stimulation of the brain could reproduce frequency and intensity as pitch and loudness in severely-to-profoundly deaf adults who originally had hearing before going deaf. Electrical stimulation at low rates (50 pulses/sec) was perceived as a pitch of the same frequency, but at rates above 200 pulses/sec, what was heard was poorly discriminated and a much higher pitch. This discovery established that the timing of electrical stimuli was important for low pitch when this had been difficult to determine with sound. But discrimination of pitch up to 4000 Hz is required for speech understanding, so Clark emphasised early in the development of his cochlear implant that "place coding through multi-channel stimulation" would have to be used for the important mid-to-high speech frequencies. Clark and Tong next discovered that place of stimulation was experienced as timbre, but without a strong pitch sensation. The patient could identify separate sensations according to the site of stimulation in the cochlea.
Just intonation
The human voice is among the most pitch-flexible instruments in common use. Pitch can be varied with no restraints and adjusted in the midst of performance, without needing to retune. Although the explicit use of just intonation fell out of favour concurrently with the increasing use of instrumental accompaniment (with its attendant constraints on pitch), most a cappella ensembles naturally tend toward just intonation because of the comfort of its stability. Barbershop quartets are a good example of this.
Cent (music)
It is difficult to establish how many cents are perceptible to humans; this accuracy varies greatly from person to person. One author stated that humans can distinguish a difference in pitch of about 5–6 cents. The threshold of what is perceptible, technically known as the just noticeable difference (JND), also varies as a function of the frequency, the amplitude and the timbre. In one study, changes in tone quality reduced student musicians' ability to recognize, as out-of-tune, pitches that deviated from their appropriate values by ±12 cents. It has also been established that increased tonal context enables listeners to judge pitch more accurately. Free, online web sites for self-testing are available. "While intervals of less than a few cents are imperceptible to the human ear in a melodic context, in harmony very small changes can cause large changes in beats and roughness of chords."
Ernst Terhardt
According to Terhardt’s theory of pitch perception, pitch perception can be divided into two separate stages: auditory spectral analysis and harmonic pitch pattern recognition. In the first stage, the inner ear (cochlea and basilar membrane) performs a running spectral analysis of the incoming signal. The parameters of this analysis (e.g. the effective length and shape of the analysis window) depend directly on physiology and indirectly on the co-evolution of ear and voice as our human and prehuman ancestors interacted with their social and physical environments. The output of this first stage is called a spectral pitch pattern, when it is determined by psychoacoustic experiments in which listeners make subjective judgments, matching the perceived pitch of a pure reference tone to that of a successively presented complex tone. The spectral pitches differ in perceptual salience since their sound pressure levels differ physically, they lie at different distances above the threshold of hearing, they mask each other (and therefore lie at different distances above the masked threshold), and may or may not lie in a region to which the ear is particularly sensitive (a dominance region of pitch perception). A cornerstone of Terhardt’s is approach is the idea that because spectral pitches are subjective, we must not jump to conclusions about the relationship between them and their physiological (physical) foundations in the ear and brain.
Ultrasound
Toothed whales, including dolphins, can hear ultrasound and use such sounds in their navigational system (biosonar) to orient and to capture prey. Porpoises have the highest known upper hearing limit at around 160 kHz. Several types of fish can detect ultrasound. In the order Clupeiformes, members of the subfamily Alosinae (shad) have been shown to be able to detect sounds up to 180 kHz, while the other subfamilies (e.g. herrings) can hear only up to 4 kHz.
Sending loudness rating
20 micro-Pascals is called the Threshold of human hearing, and is equal to 0 dB Sound pressure level (SPL).
Music
Pitch is an aspect of a sound that we can hear, reflecting whether one musical sound, note or tone is "higher" or "lower" than another musical sound, note or tone. We can talk about the highness or lowness of pitch in the more general sense, such as the way a listener hears a piercingly high piccolo note or whistling tone as higher in pitch than a deep thump of a bass drum. We also talk about pitch in the precise sense associated with musical melodies, basslines and chords. Precise pitch can only be determined in sounds that have a frequency that is clear and stable enough to distinguish from noise. For example, it is much easier for listeners to discern the pitch of a single note played on a piano than to try to discern the pitch of a crash cymbal that is struck.
A melody (also called a "tune") is a series of pitches (notes) sounding in succession (one after the other), often in a rising and falling pattern. The notes of a melody are typically created using pitch systems such as scales or modes. Melodies also often contain notes from the chords used in the song. The melodies in simple folk songs and traditional songs may use only the notes of a single scale, the scale associated with the tonic note or key of a given song. For example, a folk song in the key of C (also referred to as C major) may have a melody that uses only the notes of the C major scale (the individual notes C, D, E, F, G, A, B and C; these are the "white notes" on a piano keyboard. On the other hand, Bebop-era jazz from the 1940s and contemporary music from the 20th and 21st centuries may use melodies with many chromatic notes (i.e., notes in addition to the notes of the major scale; on a piano, a chromatic scale would include all the notes on the keyboard, including the "white notes" and "black notes" and unusual scales, such as the whole tone scale (a whole tone scale in the key of C would contain the notes C, D, E, F, G and A). A low, deep musical line played by bass instruments such as double bass, electric bass or tuba is called a bassline.
Psychoacoustics
Frequency resolution of the ear is 3.6 Hz within the octave of That is, changes in pitch larger than 3.6 Hz can be perceived in a clinical setting. However, even smaller pitch differences can be perceived through other means. For example, the interference of two pitches can often be heard as a repetitive variation in volume of the tone. This amplitude modulation occurs with a frequency equal to the difference in frequencies of the two tones and is known as beating.
Absolute pitch
Absolute pitch is the ability to perceive pitch class and to mentally categorize sounds according to perceived pitch class. A pitch class is the set of all pitches that are a whole number of octaves apart. While the boundaries of musical pitch categories vary among human cultures, the recognition of octave relationships is a natural characteristic of the mammalian auditory system. Accordingly, absolute pitch is not the ability to estimate a pitch value from the dimension of pitch-evoking frequency (30–5000 Hz), but to identify a pitch class category within the dimension of pitch class (e.g., C-C-D ... B-C).
Infrasound
20 Hz is considered the normal low-frequency limit of human hearing. When pure sine waves are reproduced under ideal conditions and at very high volume, a human listener will be able to identify tones as low as 12 Hz. Below 10 Hz it is possible to perceive the single cycles of the sound, along with a sensation of pressure at the eardrums.
Scientific pitch
Scientific pitch, also known as philosophical pitch, Sauveur pitch or Verdi tuning, is an absolute concert pitch standard which is based on middle C (C4) being set to 256 Hz rather than 261.62 Hz, making it approximately 37.6 cents lower than the common A440 pitch standard. It was first proposed in 1713 by French physicist Joseph Sauveur, promoted briefly by Italian composer Giuseppe Verdi in the 19th century, then advocated by the Schiller Institute beginning in the 1980s.
Hertz
Sound is a traveling longitudinal wave which is an oscillation of pressure. Humans perceive frequency of sound waves as pitch. Each musical note corresponds to a particular frequency which can be measured in hertz. An infant's ear is able to perceive frequencies ranging from 20 Hz to 20,000 Hz; the average adult human can hear sounds between 20 Hz and 16,000 Hz. The range of ultrasound, infrasound and other physical vibrations such as molecular and atomic vibrations extends from a few femtohertz into the terahertz range and beyond.
Contemporary architecture
The Elbphilharmonie concert hall in Hamburg, Germany, by Herzog & de Meuron, which was inaugurated in January, 2017, is the tallest inhabited building in the city, with a height of 110 meters (360 ft). The glass concert hall, which has 2100 seats in Vineyard style, is perched atop a former warehouse. One side of the concert hall building contains a hotel, while the structure on the other side above the concert hall contains forty five apartments. The concert hall in the middle is isolated from the sound of the other parts of the building by an "eggshell" of plaster and paper panels and insulation resembling feather pillows.
Underwater acoustics
Dolphins and other toothed whales are known for their acute hearing sensitivity, especially in the frequency range 5 to 50 kHz. Several species have hearing thresholds between 30 and 50 dB re 1 μPa in this frequency range. For example, the hearing threshold of the killer whale occurs at an RMS acoustic pressure of 0.02 mPa (and frequency 15 kHz), corresponding to an SPL threshold of 26 dB re 1 μPa.
Absolute threshold of hearing
The threshold of hearing is generally reported as the RMS sound pressure of 20 micropascals, corresponding to a sound intensity of 0.98 pW/m at 1 atmosphere and 25 °C. It is approximately the quietest sound a young human with undamaged hearing can detect at 1,000 Hz. 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, where the threshold reaches as low as −9 dB SPL.
Pitch (music)
Standard pitch is a more widely accepted convention. The A above middle C is usually set at 440 Hz (often written as "A = 440 Hz" or sometimes "A440"), although other frequencies, such as 442 Hz, are also often used as variants. Another standard pitch, the so-called "Baroque pitch", has been set in the 20th century as A = 415 Hz—approximately an equal-tempered semitone lower than A440 to facilitate transposition.
Auditory imagery
Humans retain a relatively strong auditory image for details in pitch, which can be improved with musical training. The development of cultivating an auditory image with absolute pitch, which is being able to determine a note upon hearing a sound, however, is dependent on childhood musical training and genetic factors. People are able to improve their discrimination of pitch; however, they cannot improve their detection. Auditory image pitch detection studies have shown that response time decreases when judging two high pitches as opposed to judging two low pitches.
Human height
The people of the Dinaric Alps, mainly South Slavs (Montenegro and East Herzegovina), are on record as being the tallest in the world, with a male average height of 185.6 cm (6 ft 1.1 in) and female average height of 170.9 cm (5 ft 7.3 in).
Missing fundamental
Most common telephones cannot reproduce sounds lower than 300 Hz, but a male voice has a fundamental frequency approximately 150 Hz. Because of the missing fundamental effect, the fundamental frequencies of male voices are still perceived as their pitches over the telephone.
Hyperbass flute
The hyperbass flute is an extremely rare and the largest and lowest pitched instrument in the flute family, with tubing reaching over in length. It is pitched in C, four octaves below the concert flute (three octaves below the bass flute, two octaves below the contrabass flute, and one octave below the double contrabass flute), with its lowest note being C, one octave below the lowest C on a standard piano. At 16 hertz, this is below what is generally considered the range of human hearing (20 to 20,000 Hz).
Whistling
According to Guinness World Records, the highest pitch human whistle ever recorded was measured at 4,186 Hz, which corresponds to a C8 musical note. This was done by Michael Stuart in Richmond, Virginia, on January 11, 2016. The lowest pitch whistle ever recorded was measured at 174.6 Hz, which corresponds to a F3 musical note. This was accomplished by Jennifer Davies of Dachau, Germany on November 6, 2005. The most people whistling simultaneously was 853, which was organized at the Spring Harvest event at Minehead, UK on April 11, 2014.
Music-related memory
Absolute pitch (AP) is the ability to produce or recognize specific pitches without reference to an external standard. People boasting AP have internalized pitch references, and thus are able to maintain stable representations of pitch in long-term memory. AP is regarded as a rare and somewhat mysterious ability, occurring in as few as 1 in 10,000 people. A method commonly used to test for AP is as follows: subjects are first asked to close their eyes and imagine that a specific song is playing in their heads. Encouraged to start anywhere in the tune they like, subjects are then instructed to try to reproduce the tones of that song by singing, humming, or whistling. Productions made by the subject are then recorded on digital audio tape, which accurately preserves the pitches they sing avoiding the potential pitch and speed fluctuations of analog recording. Lastly, the subjects' productions are compared to the actual tones sung by the artists on the CDs. Errors are measured in semitone deviations from the correct pitch. This test, however, does not determine whether or not the subject has true absolute pitch, but rather is a test of implicit absolute pitch. Where true absolute pitch is concerned, Deutsch and colleagues have shown that music conservatory students who are speakers of tone languages have a far higher prevalence of absolute pitch than do speakers of nontone languages such as English. For a test of absolute pitch see the Absolute Pitch Test developed by Deutsch and colleagues at the University of California San Diego.
Audio frequency
An audio frequency (abbreviation: AF) or audible frequency is characterized as a periodic vibration whose frequency is audible to the average human. The SI unit of audio frequency is the hertz (Hz). It is the property of sound that most determines pitch.
Gryphon Audio Designs
Gryphon products typically have a very wide frequency response, much higher than 20 kHz, which is around the threshold of what is heard by humans.
Ultrasound
The upper frequency limit in humans (approximately 20 kHz) is due to limitations of the middle ear. Auditory sensation can occur if high‐intensity ultrasound is fed directly into the human skull and reaches the cochlea through bone conduction, without passing through the middle ear.
Psychoacoustics
The intensity range of audible sounds is enormous. Human ear drums are sensitive to variations in the sound pressure, and can detect pressure changes from as small as a few micropascals (µPa) to greater than For this reason, sound pressure level is also measured logarithmically, with all pressures referenced to (or 1.97385×10 atm). The lower limit of audibility is therefore defined as but the upper limit is not as clearly defined. The upper limit is more a question of the limit where the ear will be physically harmed or with the potential to cause noise-induced hearing loss.
Micronecta scholtzi
The male of this species produces its underwater courtship song by stridulating a ridge on its penis across corrugations on its abdomen. The area involved measures only 50 micrometres across, or about the thickness of a human hair. A team of biologists and sound engineers from France and Scotland have recorded "M. scholtzi" producing sound up to 99.2 decibels, a volume comparable to a passing freight train. The noise was so unexpectedly loud that the engineers checked the calibration of their instruments. It is classified by Guinness World Records as the loudest penis. Almost all volume is lost when sound moves from water to air, but even so remains audible to humans walking along the pond shore. This species is considered the loudest of all animals for its size. Despite knowing the mechanism of its sound production, researchers are still mystified by the volume produced and feel that once the process is understood, it could open up a useful avenue in ultrasonics.
Music psychology
Absolute pitch (AP) is defined as the ability to identify the pitch of a musical tone or to produce a musical tone at a given pitch without the use of an external reference pitch. Researchers estimate the occurrence of AP to be 1 in 10,000 people. The extent to which this ability is innate or learned is debated, with evidence for both a genetic basis and for a "critical period" in which the ability can be learned, especially in conjunction with early musical training.
Dynamic range
A human is capable of hearing (and usefully discerning) anything from a quiet murmur in a soundproofed room to the loudest heavy metal concert. Such a difference can exceed 100 dB which represents a factor of 100,000 in amplitude and a factor 10,000,000,000 in power. The dynamic range of human hearing is roughly 140 dB, varying with frequency, from the threshold of hearing (around −9 dB SPL at 3 kHz) to the threshold of pain (from 120–140 dB SPL). This wide dynamic range cannot be perceived all at once, however; the tensor tympani, stapedius muscle, and outer hair cells all act as mechanical dynamic range compressors to adjust the sensitivity of the ear to different ambient levels.
Hearing range
Cats have excellent hearing and can detect an extremely broad range of frequencies. They can hear higher-pitched sounds than humans or most dogs, detecting frequencies from 55 Hz up to 79 kHz. Cats do not use this ability to hear ultrasound for communication but it is probably important in hunting, since many species of rodents make ultrasonic calls. Cat hearing is also extremely sensitive and is among the best of any mammal, being most acute in the range of 500 Hz to 32 kHz. This sensitivity is further enhanced by the cat's large movable outer ears (their "pinnae"), which both amplify sounds and help a cat sense the direction from which a noise is coming.
The hearing ability of a dog is dependent on breed and age, though the range of hearing is usually around 67 Hz to 45 kHz. As with humans, some dog breeds' hearing ranges narrow with age, such as the German shepherd and miniature poodle. When dogs hear a sound, they will move their ears towards it in order to maximise reception. In order to achieve this, the ears of a dog are controlled by at least 18 muscles, which allow the ears to tilt and rotate. 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.
Absolute pitch
Absolute pitch (AP), widely referred to as perfect pitch, is a rare auditory phenomenon characterized by the ability of a person to identify or re-create a given musical note without the benefit of a reference tone.
Georgia Brown (Brazilian singer)
Georgia Brown, pseudonym of Rossana Monti (born June 29, 1980) is an Italian Brazilian singer noted for her extensive vocal range. She was listed in the 2005 "Guinness World Records" for hitting the highest vocal note and for possessing the greatest vocal range for a female, claimed to be exactly nine octaves from sub>-E1-G10 using scientific pitch notation. However, as of 2013, Tim Storms holds the record for the widest vocal range of any human with 10 octaves, with the caveat that much of Storms's vocal range is infrasound that cannot be heard and that all of Brown's range is within the range of the human ear.
Absolute threshold
The absolute threshold of hearing is the minimum sound level of a pure tone that an average ear with normal hearing can hear with no other sound present. The absolute threshold relates to the sound that can just be heard by the organism.The threshold of hearing is generally reported as the RMS sound pressure of 20 µPa (micropascals) = 2×10 pascal (Pa). It is approximately the quietest sound a young human with undamaged hearing can detect at 1,000 Hz. The threshold of hearing is frequency dependent and it has been shown that the ear's sensitivity is best at frequencies between 1 kHz and 5 kHz.
Ultrasound
Dogs and cats' hearing range extends into the ultrasound; the top end of a dog's hearing range is about 45 kHz, while a cat's is 64 kHz. The wild ancestors of cats and dogs evolved this higher hearing range to hear high-frequency sounds made by their preferred prey, small rodents. A dog whistle is a whistle that emits ultrasound, used for training and calling dogs. The frequency of most dog whistles is within the range of 23 to 54 kHz.
Steam whistle
Loudness is a subjective perception that is influenced by sound pressure level, sound duration, and sound frequency. High sound pressure level potential has been claimed for the whistles of Vladimir Gavreau, who tested whistles as large as 1.5 meter (59-inch) diameter (37 Hz).
A 20-inch diameter ring-shaped whistle (“Ultrawhistle”) patented and produced by Richard Weisenberger sounded 124 decibels at 100 feet. The variable pitch steam whistle at the New York Wire Company in York, Pennsylvania, was entered in the Guinness Book of World Records in 2002 as the loudest steam whistle on record at 124.1dBA from a set distance used by Guinness. The York whistle was also measured at 134.1 decibels from a distance of 23-feet.
Scientific pitch notation
Although pitch notation is intended to describe sounds audibly perceptible as pitches, it can also be used to specify the frequency of non-pitch phenomena. Notes below E or higher than E are outside most humans' hearing range, although notes slightly outside the hearing range on the low end may still be indirectly perceptible as pitches due to their overtones falling within the hearing range. For an example of truly inaudible frequencies, when the Chandra X-ray Observatory observed the waves of pressure fronts propagating away from a black hole, their one oscillation every 10 million years was described by NASA as corresponding to the B fifty-seven octaves below middle C (or B).
Popoli di Tessaglia!
"" (K. 316/300b) is a recitative and aria for soprano and orchestra that Wolfgang Amadeus Mozart wrote for Aloysia Weber. It is famous for including two occurrences of a G, i.e. the G above high C, or 1568 Hz by modern concert pitch – according to the "Guinness Book of Records", the highest musical note ever scored for the human voice. (However, an A is scored in Ignaz Umlauf's "Das Irrlicht", also sung by Aloysia Weber.)
Scientific pitch notation
The octave 0 of the scientific pitch notation is traditionally called sub-contra octave, and the tone marked C in SPN is written as ",C" or "C," or "CCC" in traditional systems. Octave 0 of SPN marks the low end of what humans can actually perceive, with the average person being able to hear frequencies no lower than 20 Hz.
Encephalization quotient
Manta rays have the highest EQ among fish, and either octopuses or jumping spiders have the highest among invertebrates. Despite the jumping spider having a huge brain for its size, it is minuscule in absolute terms, and humans have a much higher EQ despite having a lower raw brain-to-body weight ratio. Mean EQs for reptiles are about one tenth of those of mammals. EQ in birds (and estimated EQ in dinosaurs) generally also falls below that of mammals, possibly due to lower thermoregulation and/or motor control demands. Estimation of brain size in "Archaeopteryx (one of the oldest known ancestors of birds)", shows it had an EQ well above the reptilian range, and just below that of living birds.
Tim Storms
Storms' Guinness World Record for the lowest note produced by a human was first certified in January 2002. Storms also holds the Guinness World Record for the widest vocal range for a male. His records have been published in the Guinness World Records 2006. He broke both of these records in August 2008. As of 2008, the new record for lowest note was 0.7973 Hz, and the new record for Widest Vocal Range For Any Human was ten octaves.
Vocal cords
The perceived pitch of a person's voice is determined by a number of different factors, most importantly the fundamental frequency of the sound generated by the larynx. The fundamental frequency is influenced by the length, size, and tension of the vocal folds. This frequency averages about 125 Hz in an adult male, 210 Hz in adult females, and over 300 Hz in children. Depth-kymography is an imaging method to visualize the complex horizontal and vertical movements of vocal folds.
Scientific pitch
In the 19th century, Italian composer Giuseppe Verdi tried to stop the increase in pitch to which orchestras were tuned. In 1874 he wrote his "Requiem" using the official French standard "diapason normal" pitch of A4 tuned to 435 Hz. Later, he indicated that 432 Hz would be slightly better for orchestras. One solution he proposed was scientific pitch. He had little success.
Schiller Institute
In 1988, the institute initiated a campaign to establish "philosophical pitch" or "scientific pitch" as the classical music concert pitch standard. This tuning system is based on middle C set at 256 Hz, making concert A 430.539 Hz rather than the most commonly used 440 Hz. The Schiller Institute calls this system "Verdi tuning" because it was Italian composer Giuseppe Verdi who first sought to stop the increase in pitch to which orchestras are tuned. However, Verdi used the French standard 435 Hz in writing his "Requiem" in 1874; later he indicated that 432 Hz was slightly more optimal. It is this A=432 Hz standard that the Schiller Institute advocates, which does not align mathematically with their stated preference for C=256 Hz. French acoustic physicist Joseph Sauveur first researched then proposed the philosophical pitch standard in 1713, more than a century before Verdi began leading orchestras. Sauveur was strongly resisted by the musicians he was working with, and the proposed standard was not adopted.
Concert pitch
Concert pitch is the pitch reference to which a group of musical instruments are tuned for a performance. Concert pitch may vary from ensemble to ensemble, and has varied widely over musical history. In the literature this is also called international standard pitch. The most common modern tuning standard uses 440 Hz for A above middle C as a reference note, with other notes being set relative to it.
Ear
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 or tracts of the central auditory system.
Cetacean intelligence
The environment where dolphins live makes experiments much more expensive and complicated than for many other species; additionally, the fact that cetaceans can emit and hear sounds (which are believed to be their main means of communication) in a range of frequencies much wider than humans can means that sophisticated equipment, which was scarcely available in the past, is needed to record and analyse them. For example, clicks can contain significant energy in frequencies greater than 110 kHz (for comparison, it is unusual for a human to be able to hear sounds above 20 kHz), requiring that equipment have a sampling rates of at least 220 kHz; MHz-capable hardware is often used.
Perception of infrasound
Infrasound is sound at frequencies lower than the low frequency end of human hearing threshold at 20 Hz. It is known, however, that humans can perceive sounds below this frequency at very high pressure levels. Infrasound can come from many natural as well as man-made sources, including weather patterns, topographic features, ocean wave activity, thunderstorms, geomagnetic storms, earthquakes, jet streams, mountain ranges, and rocket launchings. Infrasounds are also present in the vocalizations of some animals. Low frequency sounds can travel for long distances with very little attenuation and can be detected hundreds of miles away from their sources.
Absolute pitch
Scientific study of absolute pitch appears to have commenced in the 19th century, focusing on the phenomenon of musical pitch and methods of measuring it. It would have been difficult for any notion of absolute pitch to have formed earlier because pitch references were not consistent. For example, the note now known as 'A' varied in different local or national musical traditions between what would now be considered as G sharp and B flat before the standardisation of the late 19th century. While the term "absolute pitch", or "absolute ear", was in use by the late 19th century by both British and German researchers, its application was not universal; other terms such as "musical ear", "absolute tone consciousness", or "positive pitch" were also used to refer to the ability. The skill is not exclusively musical, or limited to human perception; absolute pitch has been demonstrated in animals such as bats, wolves, gerbils, and birds, for whom specific pitches facilitate identification of mates or meals.
Sound pressure
The commonly used reference sound pressure in air is
which is often considered as the threshold of human hearing (roughly the sound of a mosquito flying 3 m away). The proper notations for sound pressure level using this reference are or , but the suffix notations , , dBSPL, or dB are very common, even if they are not accepted by the SI.
Tigra
Her hearing is similarly enhanced, allowing her to hear a wider range of frequencies than a normal human as well as clearly hear sounds that would be far too faint for a human to detect. Exposure to intense, high-frequency sound is far more painful for Tigra than a normal human.
List of unexplained sounds
The sound's source was roughly triangulated to a remote point in the south Pacific Ocean west of the southern tip of South America, and the sound was detected several times by the Equatorial Pacific Ocean autonomous hydrophone array. 
According to the NOAA description, it "rises rapidly in frequency over about one minute and was of sufficient amplitude to be heard on multiple sensors, at a range of over ." The NOAA's Dr. Christopher Fox did not believe its origin was man-made, such as a submarine or bomb, nor familiar geological events such as volcanoes or earthquakes. While the audio profile of Bloop does resemble that of a living creature, the source was a mystery both because it was different from known sounds and because it was several times louder than the loudest recorded animal, the blue whale.
Absolute pitch
Absolute pitch is more common among speakers of tonal languages, such as most dialects of Chinese or Vietnamese, which often depend on pitch variation as the means of distinguishing words that otherwise sound the same—e.g., Mandarin with four possible tonal variations, Cantonese with six, Southern Min with seven or eight (depending on dialect), and Vietnamese with six. Speakers of Sino-Tibetan languages have been reported to speak a word in the same absolute pitch (within a quarter-tone) on different days; it has therefore been suggested that absolute pitch may be acquired by infants when they learn to speak a tonal language (and possibly also by infants when they learn to speak a pitch-accent language). However, the brains of tonal-language speakers do not naturally process musical sound as language; perhaps such speakers are more likely to acquire absolute pitch for musical tones when they later receive musical training. Many native speakers of a tone language, even those with little musical training, are observed to sing a given song consistently with regard to pitch. Among music students of East Asian ethnic heritage, those who speak a tone language very fluently have a much higher prevalence of absolute pitch than those who do not speak a tone language.
Infrasound
Infrasound, sometimes referred to as low-frequency sound, is sound that is lower in frequency than 20 Hz or cycles per second, the "normal" limit of human hearing. Hearing becomes gradually less sensitive as frequency decreases, so for humans to perceive infrasound, the sound pressure must be sufficiently high. The ear is the primary organ for sensing infrasound, but at higher intensities it is possible to feel infrasound vibrations in various parts of the body.
Virtual pitch
Virtual pitch is an experimentally established phenomenon in humans that can be mathematically described. In its basic form, given a series of pure tones whose frequencies correspond to a harmonic series, one will hear a virtual pitch near the fundamental frequency, even if there is no pure tone at that frequency. The perceptual salience (clarity, probability of noticing) of the virtual pitch depends on how closely the audible partials match lower harmonics above the virtual pitch. In Terhardt's pitch algorithm, virtual pitches are predicted by looking for subharmonic coincidences between audible partials in a complex tone - in other words, by looking for missing fundamentals.
Hearing range
As dogs hear higher frequency sounds than humans, they have a different acoustic perception of the world. Sounds that seem loud to humans often emit high frequency tones that can scare away dogs. Whistles which emit ultrasonic sound, called dog whistles, are used in dog training, as a dog will respond much better to such levels. In the wild, dogs use their hearing capabilities to hunt and locate food. Domestic breeds are often used to guard property due to their increased hearing ability. So-called "Nelson" dog whistles generate sounds at frequencies higher than those audible to humans but well within the range of a dog's hearing.
Plantation Harbor
The Echo drums on the track "Theme from Cabin Weirdos" were recorded on top of Mount Mitchell, which is the highest peak of the Appalachian Mountains and the highest peak in the eastern United States, the mountain reaches an elevation of 6,684 ft (2,037 m)
Transcription (music)
The pitch-detection method invented by Piszczalski again mimics human hearing. It follows how only certain sets of partials “fuse” together in human listening. These are the sets that create the perception of a single pitch only. Fusion occurs only when two partials are within 1.5% of being a perfect, harmonic pair (i.e., their frequencies approximate a low-integer pair set such as 1:2, 5:8, etc.) This near harmonic match is required of all the partials in order for a human to hear them as only a single pitch.
Acoustic microscopy
Ultrasound is broadly defined as any sound having a frequency above 20 kHz, which is approximately the highest frequency that can be detected by the human ear. However, the acoustic microscopes emit ultrasound ranging from 5 MHz to beyond 400 MHz so that micrometre size resolution can be achieved. The ultrasound that penetrates a sample may be scattered, absorbed or reflected by the internal features or the material itself. These actions are analogous to the behavior of light. Ultrasound that is reflected from an internal feature, or (in some applications) that has traveled through the entire thickness of the sample, is used to make acoustic images.
Dog whistle
The upper limit of the human hearing range is about 20 kilohertz (kHz) for children, declining to 15–17 kHz for middle-age adults. The top end of a dog's hearing range is about 45 kHz, while a cat's is 64 kHz. It is thought that the wild ancestors of cats and dogs evolved this higher hearing range in order to hear high-frequency sounds made by their preferred prey, small rodents. The frequency of most dog whistles is within the range of 23 to 54 kHz, so they are above the range of human hearing, although some are adjustable down into the audible range.
Equal-loudness contour
Fletcher and Munson first measured equal-loudness contours using headphones (1933). In their study, test subjects listened to pure tones at various frequencies and over 10 dB increments in stimulus intensity. For each frequency and intensity, the listener also listened to a reference tone at 1000 Hz. Fletcher and Munson adjusted the reference tone until the listener perceived that it was the same loudness as the test tone. Loudness, being a psychological quantity, is difficult to measure, so Fletcher and Munson averaged their results over many test subjects to derive reasonable averages. The lowest equal-loudness contour represents the quietest audible tone—the "absolute threshold of hearing". The highest contour is the "threshold of pain".
Vox Maris (musical instrument)
On 21 October 2011, Guinness World Records confirmed the Vox Maris as the loudest pipe organ in the world, producing a reading of 138.4 dbA.
Noise
A-weighting is applied to a sound spectrum to represent the sound that humans are capable of hearing at each frequency. Sound pressure is thus expressed in terms of dBA. 0 dBA is the softest level that a person can hear. Normal speaking voices are around 65 dBA. A rock concert can be about 120 dBA.
PULHES Factor
1 – Audiometer average level for each ear not more than 25 dB at 500, 1000, 2000 Hz with no individual level greater than 30 dB. Not over 45 dB at 4000 Hz.
2 – Audiometer average level for each ear at 500, 1000, 2000 Hz, or not more than 30 dB, with no individual level greater than 35 dB at these frequencies, and level not more than 55 dB at 4000 Hz; or audiometer level 30 dB at 500 Hz, 25 dB at 1000 and 2000 Hz, and 35 dB at 4000 Hz in better ear. (Poorer ear may be deaf.) 
3 – Speech reception threshold in best ear not greater than 30 dB HL, measured with or without hearing aid; or acute or chronic ear disease. 
4 – Functional level below the standards of "3".
Vocal register
The whistle register is the highest register of the human voice. The whistle register is so called because the timbre of the notes that are produced from this register are similar to that of a whistle or the upper notes of a flute, whereas the modal register tends to have a warmer, less shrill timbre. Women of all voice types can use the whistle register. With proper vocal training, it is possible for most women and some men to develop this part of the voice. Children can also phonate in the whistle register, without conscious effort.
Evolution of the cochlea
The size of cochlea has been measured throughout its evolution based on the fossil record. In one study, the basal turn of the cochlea was measured, and it was hypothesized that cochlear size correlates with body mass. The size of the basal turn of the cochlea was not different in Neanderthals and Holocene humans, however it became larger in early modern humans and Upper Paleolithic humans. Furthermore, the position and orientation of the cochlea is similar between Neanderthals and Holocene humans, relative to plane of the lateral canal, whereas early modern and upper Paleolithic humans have a more superiorly placed cochlea than Holocene humans. When comparing hominins of the Middle Pleistocene and Neanderthals and Holocene humans, the apex of the cochlea faces more inferiorly in the hominins than the latter two groups. Finally, the cochlea of European middle Pleistocene hominins faces more inferiorly than Neanderthals, modern humans, and Homo erectus.
Human beings, along with Apes, are the only mammals that do not have high frequency (>32 kHz) hearing. Humans have long cochleae, but the space devoted to each frequency range is quite large (2.5mm per octave), resulting in a comparatively reduced upper frequency limit. The human cochlea has approximately 2.5 turns around the modiolus (the axis). Humans, like many mammals and birds, are able to perceive auditory signals that displace the eardrum by a mere picometre.
Sound
Pitch is perceived as how "low" or "high" a sound is and represents the cyclic, repetitive nature of the vibrations that make up sound. For simple sounds, pitch relates to the frequency of the slowest vibration in the sound (called the fundamental harmonic). In the case of complex sounds, pitch perception can vary. Sometimes individuals identify different pitches for the same sound, based on their personal experience of particular sound patterns. Selection of a particular pitch is determined by pre-conscious examination of vibrations, including their frequencies and the balance between them. Specific attention is given to recognising potential harmonics. Every sound is placed on a pitch continuum from low to high. For example: white noise (random noise spread evenly across all frequencies) sounds higher in pitch than pink noise (random noise spread evenly across octaves) as white noise has more high frequency content. Figure 1 shows an example of pitch recognition. During the listening process, each sound is analysed for a repeating pattern (See Figure 1: orange arrows) and the results forwarded to the auditory cortex as a single pitch of a certain height (octave) and chroma (note name).
Equal-loudness contour
The human auditory system is sensitive to frequencies from about 20 Hz to a maximum of around 20,000 Hz, although the upper hearing limit decreases with age. Within this range, the human ear is most sensitive between 2 and 5 kHz, largely due to the resonance of the ear canal and the transfer function of the ossicles of the middle ear.
Auditory cortex
When each instrument of a symphony orchestra or the jazz band plays the same note, the quality of each sound is different — but the musician perceives each note as having the same pitch. The neurons of the auditory cortex of the brain are able to respond to pitch. Studies in the marmoset monkey have shown that pitch-selective neurons are located in a cortical region near the anterolateral border of the primary auditory cortex. This location of a pitch-selective area has also been identified in recent functional imaging studies in humans.
Music theory
Pitch is the lowness or highness of a tone, for example the difference between middle C and a higher C. The frequency of the sound waves producing a pitch can be measured precisely, but the perception of pitch is more complex because single notes from natural sources are usually a complex mix of many frequencies. Accordingly, theorists often describe pitch as a subjective sensation.
Bat
Microbats and a few megabats emit ultrasonic sounds to produce echoes. By comparing the outgoing pulse with the returning echoes, the brain and auditory nervous system can produce detailed images of the bat's surroundings. This allows bats to detect, localise, and classify their prey in darkness. Bat calls are some of the loudest airborne animal sounds, and can range in intensity from 60 to 140 decibels. Microbats use their larynx to create ultrasound, and emit it through the mouth and sometimes the nose. The latter is most pronounced in the horseshoe bats ("Rhinolophus" spp.). Microbat calls range in frequency from 14,000 to well over 100,000 Hz, extending well beyond the range of human hearing (between 20 and 20,000 Hz). Various groups of bats have evolved fleshy extensions around and above the nostrils, known as nose-leaves, which play a role in sound transmission.
Audio frequency
The generally accepted standard range of audible frequencies for humans is 20 to 20,000 Hz, although the range of frequencies individuals hear is greatly influenced by environmental factors. Frequencies below 20 Hz are generally felt rather than heard, assuming the amplitude of the vibration is great enough. High frequencies are the first to be affected by hearing loss due to age or prolonged exposure to very loud noises.
Decibel
Since the human ear is not equally sensitive to all sound frequencies, noise levels at maximum human sensitivity, somewhere between 2 and 4 kHz, are factored more heavily into some measurements using frequency weighting. (See also Stevens' power law.)
Tactile transducer
In the 2010s, tactile sound transducers have evolved to include higher frequencies and produce higher fidelity. The human tactile frequency range is from 1 Hz, very low frequency such as earthquakes, up to 5 kHz in some hearing impaired individuals. For most individuals 2 to 3 kHz is the upper threshold for tactile reception. These 2010s-era devices must have higher resolution than previous "shakers" to produce these frequencies. Most humans have tactile resolution to 2 Hz which is the smallest change in frequency that can be perceived. The primary use for this extended bandwidth is to reproduce the vibratory signature for musical instruments such as violins, guitars, the human voice or sound effects in movies (for example, the speeders in "Star Wars"). Also higher frequencies may be used to augment hearing through bone conduction, a consideration for people who have compromised their hearing from exposure to loud music.
Scientific pitch notation
Using scientific pitch notation consistently, the MIDI NoteOn message assigns MIDI note 0 to C (five octaves below C or Middle C; lowest note on the two largest organs of the world; about one octave below the human hearing threshold: its overtones, however, are audible), MIDI note 21 to A (the bottom key of an 88-key piano), MIDI note 60 to C (Middle C), MIDI note 69 to A (A440), MIDI note 108 to C (the top key of an 88-key piano), and MIDI note 127 to G (beyond the piano; one octave above the highest note on some keyboard glockenspiels; some notes above the highest-pitched organ pipes).
Sound
The physical reception of sound in any hearing organism is limited to a range of frequencies. Humans normally hear sound frequencies between approximately 20 Hz and 20,000 Hz (20 kHz), The upper limit decreases with age. Sometimes "sound" refers to only those vibrations with frequencies that are within the hearing range for humans or sometimes it relates to a particular animal. Other species have different ranges of hearing. For example, dogs can perceive vibrations higher than 20 kHz.
Huqin
The most common huqin are the "erhu", which are tuned to a middle range; "zhonghu", which is tuned to a lower register, and "gaohu", which is tuned to a higher pitch. The lowest pitched huqins include the dahu and gehu. The highest pitched huqin is the jinghu, used in the Beijing opera. Over eighty types of "huqin" instruments have been documented.
Hearing
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. In species that use sound as a primary means of communication, hearing is typically most acute for the range of pitches produced in calls and speech.
Pitch circularity
Pitch circularity is a fixed series of tones that appear to ascend or descend endlessly in pitch.
Pitch is often defined as extending along a one-dimensional continuum from high to low, as can be experienced by sweeping one’s hand up or down a piano keyboard. This continuum is known as pitch height. However pitch also varies in a circular fashion, known as pitch class: as one plays up a keyboard in semitone steps, C, C, D, D, E, F, F, G, G, A, A and B sound in succession, followed by C again, but one octave higher. Because the octave is the most consonant interval after the unison, tones that stand in octave relation, and are so of the same pitch class, have a certain perceptual equivalence—all Cs sound more alike to other Cs than to any other pitch class, as do all Ds, and so on; this creates the auditory equivalent of a Barber's pole.
Researchers have demonstrated that by creating banks of tones whose note names are clearly defined perceptually but whose perceived heights are ambiguous, one can create scales that appear to ascend or descend endlessly in pitch. Roger Shepard achieved this ambiguity of height by creating banks of complex tones, with each tone composed only of components that stood in octave relationship. In other words, the components of the complex tone C consisted only of Cs, but in different octaves, and the components of the complex tone F consisted only of Fs, but in different octaves. When such complex tones are played in semitone steps the listener perceives a scale that appears to ascend endlessly in pitch. Jean-Claude Risset achieved the same effect using gliding tones instead, so that a single tone appeared to glide up or down endlessly in pitch.
Circularity effects based on this principle have been produced in orchestral music and electronic music, by having multiple instruments playing simultaneously in different octaves.
Nepenthes hemsleyana
The frequency of the bats' vocalisations (starting well above 250 kHz) is the highest known of any bat species and may be an adaptation to locate pitchers among dense surrounding vegetation. The bats are likely further aided by a parabolic structure found in the rear wall of "N. hemsleyana" upper pitchers. This structure shows far stronger echo-reflection than a comparable area in the most closely related pitcher plant species, "Nepenthes rafflesiana". These reflecting structures are convergent with those of some Neotropical bat-pollinated angiosperms, such as "Marcgravia evenia".
Beluga whale
The beluga has a very specialized sense of hearing and its auditory cortex is highly developed. It can hear sounds within the range of 1.2 to 120 kHz, with the greatest sensitivity between 10 and 75 kHz, where the average hearing range for humans is 0.02 to 20 kHz. The majority of sounds are most probably received by the lower jaw and transmitted towards the middle ear. In the toothed whales, the lower jawbone is broad with a cavity at its base, which projects towards the place where it joins the cranium. A fatty deposit inside this small cavity connects to the middle ear. Toothed whales also possess a small external auditory hole a few centimetres behind their eyes; each hole communicates with an external auditory conduit and an eardrum. It is not known if these organs are functional or simply vestigial.
Hearing range
Behavioural hearing tests or physiological tests can be used to find hearing thresholds of humans and other animals. For humans, the test involves tones being presented at specific frequencies (pitch) and intensities (loudness). When the subject hears the sound, he or she indicates it by raising a hand or pressing a button. The lowest intensity they can hear is recorded. The test varies for children; their response to the sound can be indicated by a turn of the head or using a toy. The child learns what to do upon hearing the sound, such as placing a toy man in a boat. A similar technique can be used when testing animals, where food is used as a reward for responding to the sound. The information on different mammals hearing was obtained primarily by behavioural hearing tests.
Pink noise
The human auditory system, which processes frequencies in a roughly logarithmic fashion approximated by the Bark scale, does not perceive different frequencies with equal sensitivity; signals around 1–4 kHz sound loudest for a given intensity. However, humans still differentiate between white noise and pink noise with ease.
Adam Lopez
According to the "Guinness Book of World Records", Lopez held the world record for highest vocal note produced by a male from 2008 to 2018. That pitch is designated D in note-octave notation; it is three semitones above the highest note on a standard grand piano or 4435 Hz. Before achieving this record, Lopez held the previous Guinness World Record for singing a C in 2005. On January 20, 2018, the record was surpassed by Xiao Lung Wang from China recognised by Guinness World Record for singing E8 or 5,243 Hz.
Pitch contour
Pure tones have a clear pitch, but complex sounds such as speech and music typically have intense peaks at many different frequencies. Nevertheless, by establishing a fixed reference point in the frequency function of a complex sound, and then observing the movement of this reference point as the function translates, one can generate a meaningful pitch contour consistent with human experience.