What sound frequencies does a person hear? Frequency information. Judgments about the distance and direction of sounds

Hearing is the ability of the hearing organ to perceive sounds; a special function of the hearing aid, excited by sound vibrations in the environment, such as air or water. One of the biological five senses, also called acoustic perception.

General information

A person is able to hear sound ranging from 16 Hz to 20 kHz. These waves have the most important biological significance, for example, sound waves in the range of 300-4000 Hz correspond to the human voice. Sounds above 20,000 Hz are of little practical importance, as they are quickly decelerated; vibrations below 20 Hz are perceived through the tactile and vibrator sense. The range of frequencies that a person can hear is called auditory or sound range; higher frequencies are called ultrasound, and lower frequencies are called infrasound.

Physiology of hearing

The ability to distinguish sound frequencies greatly depends on the individual: his age, gender, susceptibility to hearing diseases, training. Individuals are capable of perceiving sound up to 22 kHz, and possibly higher.

Some animals can hear ultra- and/or infrasound. Bats use ultrasound for echolocation during flight. Dogs are able to hear ultrasound, which is what silent whistles work on. There is evidence that whales and elephants can use infrasound to communicate.

A person can distinguish several sounds at the same time due to the fact that there can be several standing waves in the cochlea at the same time.

« Explaining the phenomenon of hearing satisfactorily has proven to be an extraordinarily difficult task. The person who presented a theory that explained the perception of pitch and loudness of sound was almost certainly guaranteed a Nobel Prize.»

Psychophysiology of hearing

In, like in most mammals, the hearing organ is the ear. Many other animals also have hearing, thanks to similar ear organs or even a combination of different organs, which can differ significantly in their structure.

Auditory traces, fusion of auditory sensations

Experience proves that the sensation caused by some short sound lasts for some time in the form of a trace after the cessation of the external shock that caused it. Therefore, two sounds that quickly follow each other give a single auditory sensation, which is the result of their fusion. But auditory traces turn out to be more short-lived than visual ones: while the latter merge already with a tenfold repetition per second, to merge auditory sensations, their repetition is required at least 130 times per second. In other words, the light trail lasts 1/10 of a second, while the auditory trail lasts about 1/130 of a second. The fusion of auditory sensations is of great importance in the clarity of the perception of sounds and in matters of consonance and dissonance, which play such a huge role in music.

Projecting outward auditory sensations

No matter how auditory sensations arise, we usually attribute them to the external world, and therefore we always look for the reason for the stimulation of our hearing in vibrations received from the outside from one distance or another. This trait in the sphere of hearing is much less pronounced than in the sphere of visual sensations, which are distinguished by their objectivity and strict spatial localization and, probably, is also acquired through long experience and control of other senses. With auditory sensations, the ability for projection, objectification and spatial localization in the field of hearing cannot reach such high degrees as with visual sensations. This is due to the structural features of the hearing aid, for example, such as a lack of muscle mechanisms, which deprives it of the ability to make accurate spatial determinations. The enormous importance that muscular sense plays in all spatial definitions is well known.

Judgments about the distance and direction of sounds

Our judgments about the distance at which sounds are made are very inaccurate, especially when blindfolded, when you cannot see the source of the sounds. This especially applies to sounds unknown to us; familiar sounds seem closer to us the louder they are, and vice versa. Experience shows that we are less mistaken in determining the distance of noise than of musical tones. Regarding judgments about the direction of sounds, this ability also turns out to be limited in humans; not having mobile ears that are convenient for collecting sounds, in doubtful cases he resorts to head movements and puts it in a position in which sounds are best distinguished, and localizes the sound in the direction from which it is heard stronger and more clearly.

There are two known mechanisms by which the direction of sound can be distinguished:

• Branched neurons are able to distinguish time delays between the arrival of sound waves in the right and left ears. (About 10 µs)
• For high frequencies, such that the sound wavelength is smaller than the size of the listener, the sound reaching the near ear has greater intensity.

Moreover, the first mechanism has more weight than the second.

Both of these mechanisms do not work well in water, since the speed of sound in it is much greater than in air.

Hearing test

Hearing is tested using a special device or computer program called an audiometer.

It is possible to determine the leading ear using special tests. For example, different audio signals (words) are fed into the headphones, and a person records them on paper. Whichever ear has the most correctly recognized words is the leading ear.

The perception of the frequency range 16 Hz-20 kHz changes with age (high frequencies are perceived worse and worse)

The person is deteriorating, and over time we lose the ability to detect a certain frequency.

Video made by the channel AsapSCIENCE, is a kind of age-related hearing loss test that will help you find out your hearing limits.

Various sounds are played in the video, starting at 8000 Hz, which means your hearing is not impaired.

The frequency then increases and this indicates the age of your hearing based on when you stop hearing a particular sound.

So if you hear a frequency:

12,000 Hz – you are under 50 years old

15,000 Hz – you are under 40 years old

16,000 Hz – you are under 30 years old

17,000 – 18,000 – you are under 24 years old

19,000 – you are under 20 years old

If you want the test to be more accurate, you should set the video quality to 720p or better yet 1080p, and listen with headphones.

Hearing test (video)

Hearing loss

If you heard all the sounds, you are most likely under 20 years old. Results depend on sensory receptors in your ear called hair cells which become damaged and degenerate over time.

This type of hearing loss is called sensorineural hearing loss. A variety of infections, medications, and autoimmune diseases can cause this disorder. The outer hair cells, which are tuned to detect higher frequencies, are usually the first to die, causing the effects of age-related hearing loss, as demonstrated in this video.

Human hearing: interesting facts

1. Among healthy people frequency range that the human ear can detect ranges from 20 (lower than the lowest note on a piano) to 20,000 Hertz (higher than the highest note on a small flute). However, the upper limit of this range decreases steadily with age.

2. People talk to each other at a frequency from 200 to 8000 Hz, and the human ear is most sensitive to a frequency of 1000 – 3500 Hz

3. Sounds that are above the limit of human audibility are called ultrasound, and those below - infrasound.

4. Ours my ears don't stop working even in my sleep, continuing to hear sounds. However, our brain ignores them.

5. Sound travels at 344 meters per second. A sonic boom occurs when an object exceeds the speed of sound. Sound waves in front and behind the object collide and create a shock.

6. Ears - self-cleaning organ. Pores in the ear canal secrete earwax, and tiny hairs called cilia push the wax out of the ear

7. The sound of a baby crying is approximately 115 dB, and it's louder than a car horn.

8. In Africa there is a Maaban tribe who live in such silence that even in old age they hear whispers up to 300 meters away.

9. Level bulldozer sound idling is about 85 dB (decibels), which can cause hearing damage after just one 8-hour day.

10. Sitting in front speakers at a rock concert, you're exposing yourself to 120 dB, which begins to damage your hearing after just 7.5 minutes.

Test your hearing in 5 minutes without leaving home!

The Internet is again divided into two camps, which has not happened since the days of the famous “dress of discord”, the color of which people perceived differently. Now users are occupied with a new riddle, which is based on an audio fragment.

The new phenomenon was first discussed on the Reddit forum on April 13. The author's post included a video of a robotic voice saying the name. But users just can’t agree on which one - the fact is that half of the forum hears Yanny, and the other half hears Laurel.

The most popular comment on this post calls the video "black magic." What adds to the mystique of this situation is not only the fact that “Yenny” and “Laurel” sound different in principle, but also the fact that the same person can hear two different names if he listens to the recording several times.

Some users sincerely cannot understand how this is possible and do not believe those who hear a different name. Of course, several scientists from different scientific fields have already joined in solving the phenomenon, but they cannot yet agree.

One of the most popular versions is the one related to the frequency of sound. Maastricht University Associate Professor Lars Riecki told The Verge that “Jenny” sounds at higher frequencies, while “Laurel” sounds at lower frequencies. As a result, people who are more sensitive to high-frequency sounds hear “Yenny,” while others hear “Laurel.”

The same situation is observed with those who listen to the recording on different devices or in different headphones - due to the frequency, the perception of the same person can change dramatically.

In addition, some users believe that the whole point is in the playback speed - the mysterious recording was placed in a video editor and played at different tempos. Thus, most users hear “Yenny” at the beginning of the video and “Laurel” towards the end. Unfortunately, not everything is clear here either - the editors of Gazeta.Ru conducted an experiment and found out that people begin to hear the name “Laurel” at different speeds, and some do not hear it at all.

There is another version. A group of scientists believes that due to poor recording quality, the hearing aid of different people perceives audio ambiguously - the brain does not have enough information and it independently “invents” the missing sounds.

It is also reported that older people hear only one variant (usually “Yenny”), as hearing deteriorates over time and can no longer interpret sounds ambiguously.

Finally, one more circumstance is the expectation of the listener himself. The author of the text has heard both “Yenny” and “Laurel” several times, if on the eve of listening to focus on only one possible option.

What color is the dress

The new sound illusion is a continuation of the “dress of discord” that broke the entire Internet in February 2015. Then people could not decide what color the dress shown in the photograph was - blue-black or white-gold.

wired.com

Ordinary users, scientists and even celebrities joined the discussion. As it turned out later, the biological characteristics of the human body are to blame - people perceive light in photographs differently. Those who see a blue-black dress assume that black appears brownish or even golden when exposed to bright colors.

Another "team" that claims the dress is actually white implies that it is in shadow because the light source is behind it. In this case, pure white color begins to give off a blue tint and therefore appears bluish.

Two years later, the “sneakers of discord” appeared, which again made people quarrel over different color perceptions. The British woman posted a photo of shoes that seemed pink and white to her. Her friend, on the contrary, claimed that the sneakers were gray with turquoise accents. The girl posted the photo on Facebook to find out the opinion of her friends, which again split the Internet into two camps.

If you hear some sounds that other people cannot hear, this does not mean that you are having auditory hallucinations and it’s time to see a psychiatrist. Perhaps you belong to the category of so-called “hammers”. The term comes from the English word “hum” (“hum, buzz, buzz”).

Strange complaints

The phenomenon was first noticed in the 50s of the last century: people living in different parts of the planet complained that they constantly heard a certain uniform humming sound. Most often, residents of rural areas talked about this. They claimed that the strange sound intensifies at night (apparently because at this time the overall sound background decreases). Those who heard it often experienced side effects - headache, nausea, dizziness, nosebleeds and insomnia.

In 1970, 800 Britons complained about a mysterious noise. Similar episodes also occurred in New Mexico and Sydney.

In 2003, acoustics specialist Jeff Leventhal discovered that only 2% of all inhabitants of the Earth can hear strange sounds. Mostly these are people aged 55 to 70 years. In one case, a Hamer even committed suicide because he could not bear the incessant noise.

“It’s a kind of torture, sometimes you just want to scream,” this is how Katie Jacques from Leeds (Great Britain) described her feelings. - It's hard to sleep because I hear this pulsating sound continuously. You start tossing and turning and think about it even more.”

Where is the noise coming from?

Researchers have been trying to find the source of the noise for a long time. In the early 1990s, researchers at the Los Alamos National Laboratory at the University of New Mexico concluded that hummers heard sounds from moving vehicles and factories. But this version is controversial: after all, as mentioned above, most Hamers live in rural areas.

According to another version, there is actually no hum: it is an illusion generated by a diseased brain. Finally, the most interesting hypothesis suggests that some people are highly sensitive to low-frequency electromagnetic radiation or seismic activity. That is, they hear the “hum of the Earth,” which most people do not pay attention to.

Paradoxes of hearing

The fact is that the average person is able to perceive sounds in the range from 16 hertz to 20 kilohertz, if sound vibrations are transmitted through the air. When sound is transmitted through the bones of the skull, the range increases to 220 kilohertz.

For example, the vibrations of the human voice can vary between 300-4000 hertz. We perceive sounds above 20,000 hertz worse. And fluctuations below 60 hertz are perceived by us as vibrations. High frequencies are called ultrasound, low frequencies are called infrasound.

Not all people respond the same way to different sound frequencies. This depends on many individual factors: age, gender, heredity, the presence of hearing pathologies, etc. Thus, it is known that there are people capable of perceiving high-frequency sounds - up to 22 kilohertz and higher. At the same time, animals are sometimes able to hear acoustic vibrations in a range inaccessible to humans: bats use ultrasound for echolocation during flight, and whales and elephants supposedly communicate with each other using infrasonic vibrations. [C-BLOCK]

At the beginning of 2011, Israeli scientists found that in the human brain there are special groups of neurons that allow one to estimate the pitch of a sound down to 0.1 tones. Most animal species, with the exception of bats, do not have such “devices”. With age, due to changes in the inner ear, people begin to perceive high frequencies worse and develop sensorineural hearing loss.

But, apparently, not everything is so simple with our brain, since over the years some people stop hearing even ordinary sounds, while others, on the contrary, begin to hear something that is inaccessible to the hearing of others. [С-BLOCK]

How can we help the Hamers, since they suffer so much from their “gift”? A number of experts believe that so-called cognitive behavioral therapy could cure them. But it can only work if the problem is related exclusively to the person’s mental state. And if not?

Jeff Leventhal notes that today the Hamer phenomenon is one of the mysteries whose solution has not yet been found.

February 7, 2018

Often people (even those who are well versed in the subject) experience confusion and difficulty in clearly understanding how exactly the frequency range of sound heard by humans is divided into general categories (low, mid, high) and into narrower subcategories (upper bass, lower mid and so on.). At the same time, this information is extremely important not only for experiments with car audio, but also useful for general development. Knowledge will definitely come in handy when setting up an audio system of any complexity and, most importantly, will help to correctly assess the strengths or weaknesses of a particular acoustic system or the nuances of the music listening room (in our case, the car interior is more relevant), because it has a direct impact on the final sound. If you have a good and clear understanding of the predominance of certain frequencies in the sound spectrum by ear, then you can easily and quickly evaluate the sound of a particular musical composition, while clearly hearing the influence of room acoustics on the coloring of the sound, the contribution of the acoustic system itself to the sound, and more subtly to sort out all the nuances, which is what the ideology of “hi-fi” sound strives for.

Division of the audible range into three main groups

The terminology for dividing the audible frequency spectrum came to us partly from the musical world, partly from the scientific world, and in general it is familiar to almost everyone. The simplest and most understandable division that can test the frequency range of sound in general looks like this:

• Low frequencies. The limits of the low frequency range are within 10 Hz (lower limit) - 200 Hz (upper limit). The lower limit begins precisely at 10 Hz, although in the classical view a person is able to hear from 20 Hz (everything below falls into the infrasound region), the remaining 10 Hz can still be partially audible, and can also be felt tactilely in the case of deep low bass and even influence a person's psychological mood.
  The low-frequency range of sound has the function of enrichment, emotional saturation and final response - if the dip in the low-frequency part of the acoustics or the original recording is strong, then this will not in any way affect the recognition of a particular composition, melody or voice, but the sound will be perceived as meager, depleted and mediocre, while subjectively it will be sharper and sharper in terms of perception, since the mid and high frequencies will protrude and prevail against the background of the absence of a good rich bass region.
  
  A fairly large number of musical instruments reproduce sounds in the low frequency range, including male vocals that can go down to 100 Hz. The most pronounced instrument, which plays from the very beginning of the audible range (from 20 Hz), can safely be called the wind organ.
• Mid frequencies. The boundaries of the mid frequency range are within 200 Hz (lower limit) - 2400 Hz (upper limit). The mid-range will always be fundamental, defining and actually form the basis of the sound or music of a composition, therefore its importance is difficult to overestimate.
  This can be explained in different ways, but mainly this feature of human auditory perception is determined by evolution - it has happened over many years of our formation that the hearing aid most acutely and clearly captures the mid-frequency range, because within its boundaries lies human speech, and it is the main tool for effective communication and survival. This also explains some nonlinearity of auditory perception, always aimed at the predominance of mid-frequencies when listening to music, because our hearing aid is most sensitive to this range, and also automatically adapts to it, as if “amplifying” it more against the background of other sounds.
  
  The absolute majority of sounds, musical instruments or vocals are found in the middle range, even if a narrow range above or below is affected, the range still usually extends to the upper or lower middle. Accordingly, vocals (both male and female), as well as almost all well-known instruments, such as guitar and other strings, piano and other keyboards, wind instruments, etc., are located in the mid-frequency range.
• High frequencies. The limits of the high frequency range are within 2400 Hz (lower limit) - 30000 Hz (upper limit). The upper limit, as in the case of the low-frequency range, is somewhat arbitrary and also individual: the average person cannot hear above 20 kHz, but there are rare people with sensitivity up to 30 kHz.
  Also, a number of musical overtones can theoretically extend into the region above 20 kHz, and as is known, overtones are ultimately responsible for the color of the sound and the final timbral perception of the overall sound picture. Seemingly “inaudible” ultrasonic frequencies can clearly influence a person’s psychological state, although they will not be audible in the usual manner. Otherwise, the role of high frequencies, again by analogy with low frequencies, is more enriching and complementary. Although the high-frequency range has a much greater impact on the recognition of a particular sound, the reliability and preservation of the original timbre, than the low-frequency section. High frequencies give music tracks "airiness", transparency, purity and clarity.
  
  Many musical instruments also play in the high frequency range, including vocals that can reach the region of 7000 Hz and above with the help of overtones and harmonics. The most pronounced group of instruments in the high-frequency segment are strings and winds, and cymbals and violin reach almost the upper limit of the audible range (20 kHz) in sound.

In any case, the role of absolutely all frequencies of the range audible to the human ear is impressive and problems in the path at any frequency will most likely be clearly visible, especially to a trained hearing aid. The goal of reproducing high-precision sound of “hi-fi” class (or higher) is the reliable and maximally even sound of all frequencies with each other, as it happened at the time the phonogram was recorded in the studio. The presence of strong dips or peaks in the frequency response of the speaker system indicates that, due to its design features, it is not capable of reproducing music as originally intended by the author or sound engineer at the time of recording.

Listening to music, a person hears the combination of sounds of instruments and voices, each of which sounds in some part of the frequency range. Some instruments may have a very narrow (limited) frequency range, while for others, on the contrary, it can literally extend from the lower to the upper audible limit. It must be taken into account that despite the same intensity of sounds at different frequency ranges, the human ear perceives these frequencies with different loudness, which is again due to the mechanism of the biological structure of the hearing aid. The nature of this phenomenon is also largely explained by the biological need to adapt primarily to the mid-frequency sound range. So in practice, a sound with a frequency of 800 Hz at an intensity of 50 dB will be perceived subjectively by ear as louder compared to a sound of the same intensity, but with a frequency of 500 Hz.

Moreover, different sound frequencies flooding the audible frequency range of sound will have different threshold pain sensitivity! Pain threshold the reference is considered to be at an average frequency of 1000 Hz with a sensitivity of approximately 120 dB (may vary slightly depending on the individual characteristics of the person). As with the uneven perception of intensity at different frequencies at normal volume levels, approximately the same relationship is observed with respect to the pain threshold: it occurs most quickly at mid frequencies, but at the edges of the audible range the threshold becomes higher. For comparison, the pain threshold at an average frequency of 2000 Hz is 112 dB, while the pain threshold at a low frequency of 30 Hz will be 135 dB. The pain threshold at low frequencies is always higher than at medium and high frequencies.

A similar disparity is observed in relation to hearing threshold- this is the lower threshold after which sounds become audible to the human ear. Conventionally, the hearing threshold is considered to be 0 dB, but again it is valid for the reference frequency of 1000 Hz. If, for comparison, we take a low-frequency sound of 30 Hz, then it will become audible only at a wave radiation intensity of 53 dB.

The listed features of human auditory perception, of course, have a direct impact when the question of listening to music and achieving a certain psychological effect of perception is raised. We remember from that sounds with an intensity above 90 dB are harmful to health and can lead to degradation and significant hearing impairment. But at the same time, a sound that is too quiet and of low intensity will suffer from strong frequency unevenness due to the biological characteristics of auditory perception, which is nonlinear in nature. Thus, a musical path with a volume of 40-50 dB will be perceived as depleted, with a pronounced lack (one might say failure) of low and high frequencies. This problem has been well known for a long time; to combat it, a well-known function called tone compensation, which, through equalization, equalizes the levels of low and high frequencies close to the mid-level, thereby eliminating unwanted dip without the need to raise the volume level, making the audible frequency range of sound subjectively uniform in the degree of distribution of sound energy.

Taking into account the interesting and unique features of human hearing, it is useful to note that as the sound volume increases, the frequency nonlinearity curve levels out, and at approximately 80-85 dB (and above), sound frequencies will become subjectively equivalent in intensity (with a deviation of 3-5 dB). Although the leveling does not occur completely and a smoothed but curved line will still be visible on the graph, which will maintain a tendency towards the predominance of the intensity of the middle frequencies compared to the rest. In audio systems, such unevenness can be resolved either with the help of an equalizer, or with the help of separate volume controls in systems with separate channel amplification.

Dividing the audible range into smaller subgroups

In addition to the generally accepted and well-known division into three general groups, sometimes there is a need to consider this or that narrow part in more detail and in detail, thereby dividing the frequency range of sound into even smaller “fragments”. Thanks to this, a more detailed division has appeared, using which you can quickly and quite accurately designate the expected segment of the sound range. Consider this division:

A small selected number of instruments fall into the region of the lowest bass and especially sub-bass: double bass (40-300 Hz), cello (65-7000 Hz), bassoon (60-9000 Hz), tuba (45-2000 Hz), horns (60-5000 Hz), bass guitar (32-196 Hz), bass drum (41-8000 Hz), saxophone (56-1320 Hz), piano (24-1200 Hz), synthesizer (20-20000 Hz) , organ (20-7000 Hz), harp (36-15000 Hz), contrabassoon (30-4000 Hz). The indicated ranges take into account all instrument harmonics.

Upper Bass (80 Hz to 200 Hz) represented by the top notes of classical bass instruments, as well as the lowest audible frequencies of individual strings, such as a guitar. The upper bass range is responsible for the sensation of power and transmission of the energy potential of the sound wave. It also gives a feeling of drive; the upper bass is designed to fully reveal the percussive rhythm of dance compositions. In contrast to the lower bass, the upper bass is responsible for the speed and pressure of the bass region and the entire sound, therefore in a high-quality audio system it is always expressed quickly and sharply, like a tangible tactile blow simultaneously with the direct perception of sound.
Therefore, it is the upper bass that is responsible for the attack, pressure and musical drive, and also only this narrow segment of the sound range is able to give the listener the feeling of the legendary “punch” (from the English punch - blow), when a powerful sound is perceived as a tangible and strong blow to the chest. Thus, you can recognize a well-formed and correct fast upper bass in a music system by the high-quality development of an energetic rhythm, a collected attack and by the good design of instruments in the lower register of notes, such as cello, piano or wind instruments.

In audio systems, it is most advisable to give a segment of the upper bass range to midbass speakers with a fairly large diameter of 6.5"-10" and with good power indicators and a strong magnet. The approach is explained by the fact that it is the speakers of this configuration that will be able to fully reveal the energy potential inherent in this very demanding region of the audible range.
But don’t forget about the detail and intelligibility of sound; these parameters are just as important in the process of recreating a particular musical image. Since the upper bass is already well localized/defined in space by ear, the range above 100 Hz must be given exclusively to front-mounted speakers, which will shape and build the scene. In the upper bass segment, stereo panorama can be heard perfectly, if it is provided for by the recording itself.

The upper bass region already covers a fairly large number of instruments and even low-pitched male vocals. Therefore, among the instruments are the same ones that played low bass, but many others are added to them: toms (70-7000 Hz), snare drum (100-10000 Hz), percussion (150-5000 Hz), tenor trombone (80-10000 Hz), trumpet (160-9000 Hz), tenor saxophone (120-16000 Hz), alto saxophone (140-16000 Hz), clarinet (140-15000 Hz), alto violin (130-6700 Hz), guitar (80-5000 Hz). The indicated ranges take into account all instrument harmonics.

Lower mid (200 Hz to 500 Hz)- the most extensive area, covering most instruments and vocals, both male and female. Since the region of the lower mid range actually moves from the energetically saturated upper bass, we can say that it “takes over the baton” and is also responsible for the correct transmission of the rhythm section in conjunction with the drive, although this influence is already declining towards the pure mid range frequency
In this range, the lower harmonics and overtones that fill the voice are concentrated, so it is extremely important for the correct transmission of vocals and saturation. Also, it is in the lower middle that the entire energy potential of the performer’s voice is located, without which there will be no corresponding impact and emotional response. By analogy with the transmission of the human voice, many live instruments also hide their energy potential in this part of the range, especially those whose lower audible limit starts from 200-250 Hz (oboe, violin). The lower middle allows you to hear the melody of the sound, but does not make it possible to clearly distinguish instruments.

Accordingly, the lower middle is responsible for the correct design of most instruments and voices, saturating the latter and making them recognizable by their timbre coloring. Also, the lower mids are extremely demanding with regard to the correct transmission of the full bass range, since it “picks up” the drive and attack of the main striking bass and is supposed to properly support it and smoothly “finish” it, gradually reducing it to nothing. The sensations of sound purity and bass intelligibility lie precisely in this area, and if there are problems in the lower middle due to excess or the presence of resonant frequencies, then the sound will tire the listener, it will be dirty and slightly booming.
If there is a shortage in the lower mids, then the correct feeling of the bass and the reliable transmission of the vocal part will suffer, which will be devoid of pressure and energy return. The same applies to most instruments, which without the support of the lower middle will lose “their face”, will become incorrectly shaped and their sound will noticeably become poorer, even if it remains recognizable, it will no longer be as complete.

When building an audio system, the range of the lower middle and above (up to the upper) is usually given to mid-frequency speakers (MF), which, without a doubt, should be located in the front part in front of the listener and build the stage. For these speakers, the size is not so important, it can be 6.5" or lower, but detail and the ability to reveal the nuances of sound are important, which is achieved by the design features of the speaker itself (diffuser, suspension and other characteristics).
Also, for the entire mid-frequency range, correct localization is vitally important, and literally the slightest tilt or rotation of the speaker can have a noticeable impact on the sound from the point of view of correct realistic recreation of the images of instruments and vocals in space, although this will largely depend on the design features of the speaker cone itself.

The lower middle covers almost all existing instruments and human voices, although it does not play a fundamental role, but is still very important for the full perception of music or sounds. Among the instruments there will be the same set that was capable of playing the lower range of the bass region, but others are added to them that start from the lower middle: cymbals (190-17000 Hz), oboe (247-15000 Hz), flute (240-17000 Hz), 14500 Hz), violin (200-17000 Hz). The indicated ranges take into account all instrument harmonics.

Mid mid (500 Hz to 1200 Hz) or simply a pure middle, almost according to the theory of equilibrium, this segment of the range can be considered fundamental and fundamental in sound and rightly called the “golden mean”. In the presented segment of the frequency range you can find the fundamental notes and harmonics of the absolute majority of instruments and voices. The clarity, intelligibility, brightness and shrillness of the sound depend on the saturation of the middle. We can say that the entire sound seems to “spread” to the sides from the base, which is the mid-frequency range.

If the middle fails, the sound becomes boring and inexpressive, loses its sonority and brightness, the vocals cease to bewitch and actually fade away. The middle is also responsible for the intelligibility of basic information coming from instruments and vocals (to a lesser extent, since consonant sounds are higher in the range), helping to distinguish them well by ear. Most existing instruments come to life in this range, becoming energetic, informative and tangible, and the same happens with vocals (especially female ones), which are filled with energy in the middle.

The mid-frequency fundamental range covers the vast majority of instruments that have already been listed earlier, and also reveals the full potential of male and female vocals. Only a few selected instruments begin their life at medium frequencies, playing in a relatively narrow range initially, for example, the small flute (600-15000 Hz).

Upper mids (1200 Hz to 2400 Hz) represents a very delicate and demanding section of the range that must be handled with care and caution. In this area, there are not many fundamental notes that form the foundation of the sound of an instrument or voice, but a large number of overtones and harmonics, thanks to which the sound is colored, acquires sharpness and a bright character. By controlling this area of ​​the frequency range, you can actually play with the color of the sound, making it either lively, sparkling, transparent and sharp; or, on the contrary, dryish, moderate, but at the same time more assertive and driving.

But overemphasizing this range has an extremely undesirable effect on the sound picture, because it begins to noticeably hurt the ear, irritate and even cause painful discomfort. Therefore, the upper middle requires a delicate and careful attitude, because Because of problems in this area, it is very easy to ruin the sound, or, on the contrary, to make it interesting and worthy. Typically, the color in the upper middle area largely determines the subjective genre of the speaker system.

Thanks to the upper middle, vocals and many instruments are finally formed, they become clearly distinguishable by ear and sound intelligibility appears. This is especially true for the nuances of reproducing the human voice, because it is in the upper middle that the spectrum of consonant sounds is placed and the vowels that appeared in the early ranges of the middle continue. In a general sense, the upper midrange favorably emphasizes and fully reveals those instruments or voices that are rich in upper harmonics and overtones. In particular, female vocals and many bowed, stringed and wind instruments are revealed truly vividly and naturally in the upper middle.

The upper middle is still played by the vast majority of instruments, although many are already represented only in the form of wrappers and harmonics. The exception is some rare ones, initially characterized by a limited low-frequency range, for example, the tuba (45-2000 Hz), which ends its existence completely in the upper middle.

Low Treble (2400 Hz to 4800 Hz)- this is a zone/region of increased distortion, which, if present in the path, usually becomes noticeable in this particular segment. Also, the lower highs are flooded with various harmonics of instruments and vocals, which at the same time play a very specific and important role in the final design of the musical image recreated artificially. The lower highs carry the main load of the high-frequency range. In the sound they manifest themselves mostly as residual and easily audible harmonics of vocals (mostly female) and persistent strong harmonics of some instruments, which complete the image with the final touches of natural sound coloring.

They practically do not play a role in distinguishing instruments and recognizing voices, although the lower upper remains an extremely informative and fundamental area. Essentially, these frequencies outline the musical images of instruments and vocals, they indicate their presence. If the lower high segment of the frequency range fails, the speech will become dry, lifeless and incomplete, approximately the same thing happens with instrumental parts - brightness is lost, the very essence of the sound source is distorted, it becomes clearly unfinished and under-formed.

In any normal audio system, the role of high frequencies is taken over by a separate speaker called a tweeter (high-frequency). Usually small in size, it is undemanding in terms of power input (within reasonable limits) similar to the middle and especially the low-end sections, but it is also extremely important for the sound to play correctly, realistically and at least beautifully. The tweeter covers the entire audible high-frequency range from 2000-2400 Hz to 20,000 Hz. In the case of high-frequency speakers, almost by analogy with the midrange section, the correct physical location and directionality is very important, since tweeters are maximally involved not only in the formation of the sound stage, but also in the process of fine-tuning it.

With the help of tweeters, you can control the stage in many ways, bring performers closer/farther away, change the shape and presentation of instruments, play with the color of the sound and its brightness. As in the case of adjusting midrange speakers, the correct sound of tweeters is affected by almost everything, and often very, very sensitively: the rotation and tilt of the speaker, its vertical and horizontal location, distance from nearby surfaces, etc. However, the success of proper tuning and the finickiness of the HF section depends on the design of the speaker and its polar pattern.

Instruments that play to the lower treble do so primarily through harmonics rather than fundamental notes. Otherwise, in the lower-high range, almost all of the same ones “live” as were in the mid-frequency segment, i.e. almost all existing ones. The same goes for the voice, which is especially active in the lower high frequencies, with particular brightness and influence being heard in female vocal parts.

Upper Treble (9600 Hz to 30000 Hz) a very complex and for many incomprehensible range, providing mostly support for certain instruments and vocals. The upper highs primarily provide the sound with characteristics of airiness, transparency, crystallineness, some sometimes subtle addition and coloring, which may seem insignificant and even inaudible to many people, but at the same time still carries a very definite and specific meaning. When trying to create a high-class “hi-fi” or even “hi-end” sound, the highest attention is paid to the upper high frequency range, because It is rightly believed that not the slightest detail can be lost in sound.

In addition, in addition to the immediate audible part, the region of the upper highs, smoothly turning into ultrasonic frequencies, can still have a certain psychological effect: even if these sounds are not heard clearly, the waves are emitted into space and can be perceived by a person, while more at the level mood formation. They also ultimately affect the sound quality. In general, these frequencies are the most subtle and gentle in the entire range, but they are also responsible for the feeling of beauty, elegance, and sparkling aftertaste of music. If there is a lack of energy in the upper high range, it is quite possible to feel discomfort and musical understatement. In addition, the capricious range of the upper treble gives the listener a sense of spatial depth, as if immersed deep into the stage and enveloping the sound. However, an excess of sound saturation in the designated narrow range can make the sound excessively “sandy” and unnaturally thin.

When discussing the upper high frequency range, it is also worth mentioning the tweeter called a “super tweeter”, which is actually a structurally expanded version of a regular tweeter. Such a speaker is designed to cover a larger part of the range in the upper direction. If the operating range of a conventional tweeter ends at the supposed limiting mark, above which the human ear theoretically does not perceive sound information, i.e. 20 kHz, then the super tweeter can raise this limit to 30-35 kHz.

The idea behind the implementation of such a sophisticated speaker is very interesting and curious, it comes from the world of “hi-fi” and “hi-end”, where it is believed that no frequencies can be ignored in the musical path and, even if we do not hear them directly, they are still initially present during the live performance of a particular composition, which means they can indirectly have some influence. The situation with a super tweeter is complicated only by the fact that not all equipment (sound sources/players, amplifiers, etc.) are capable of outputting a signal in the full range, without cutting off frequencies from above. The same is true for the recording itself, which is often done with frequency range cutting and loss of quality.

The division of the audible frequency range into conventional segments in reality looks approximately this way as described above; with the help of division, it is easier to understand problems in the sound path in order to eliminate them or to level out the sound. Despite the fact that each person imagines some unique standard image of sound that is understandable only to him, in accordance only with his taste preferences, the nature of the original sound tends to balance, or rather to the averaging of all sounding frequencies. Therefore, the correct studio sound is always balanced and calm, the entire spectrum of sound frequencies in it tends to a flat line on the frequency response (amplitude-frequency response) graph. The same direction is trying to implement uncompromising “hi-fi” and “hi-end”: to obtain the most even and balanced sound, without peaks and dips throughout the entire audible range. Such a sound may seem boring and inexpressive in nature to the average inexperienced listener, lacking brightness and of no interest, but it is precisely this sound that is truly correct in fact, striving for balance by analogy with how the laws of the universe itself in which we live manifest themselves .

One way or another, the desire to recreate a certain sound character within the framework of one’s audio system lies entirely on the preferences of the listener himself. Some people like a sound with a predominance of powerful lows, others like the increased brightness of “raised” highs, others can spend hours enjoying harsh vocals emphasized in the middle... There can be a huge number of perception options, and information about the frequency division of the range into conditional segments will just help anyone who wants to create the sound of their dreams, only now with a more complete understanding of the nuances and subtleties of the laws to which sound as a physical phenomenon is subject.

Understanding the process of saturation with certain frequencies of the sound range (filling it with energy in each of the sections) in practice will not only facilitate the setup of any audio system and make it possible to build a stage in principle, but will also provide invaluable experience in assessing the specific nature of the sound. With experience, a person will be able to instantly identify sound defects by ear, and very accurately describe the problems in a certain part of the range and suggest a possible solution to improve the sound picture. Sound adjustment can be carried out using various methods, where you can use an equalizer as “levers,” for example, or “play” with the location and direction of the speakers - thereby changing the nature of early wave reflections, eliminating standing waves, etc. This will be a “completely different story” and a topic for separate articles.

Frequency range of the human voice in musical terminology

The human voice plays a separate and distinct role in music as a vocal part, because the nature of this phenomenon is truly amazing. The human voice is so multifaceted and its range (in comparison with musical instruments) is the widest, with the exception of some instruments, such as the piano.
Moreover, at different ages a person can produce sounds of different pitches, in childhood up to ultrasonic heights, in adulthood a man’s voice is quite capable of falling extremely low. Here, as before, the individual characteristics of a person’s vocal cords are extremely important, because There are people who can amaze with their voices in the range of 5 octaves!

Children's
• Alto (low)
• Soprano (high)
• Treble (high for boys)

Men's
• Bass profundo (super low) 43.7-262 Hz
• Bass (low) 82-349 Hz
• Baritone (medium) 110-392 Hz
• Tenor (high) 132-532 Hz
• Tenor-altino (super high) 131-700 Hz

Women's
• Contralto (low) 165-692 Hz
• Mezzo-soprano (medium) 220-880 Hz
• Soprano (high) 262-1046 Hz
• Coloratura soprano (super high) 1397 Hz