What Is Hearing Range?

In a very quiet situation, the minimum sound intensity that a person can just hear at a certain frequency is the hearing threshold, and the sound that causes auditory pain is the pain threshold. In between, it is the human auditory response range. Hearing.

Auditory response range

Auditory response range

The sensitivity of the human ear to the position, loudness, tonality, and timbre of the sound is different, and there are large differences.

Auditory response range

The human ear has a strong ability to identify the direction and distance of sound propagation, and it can accurately identify the position of the sound source regardless of which direction the sound comes from. This hearing characteristic of the human ear is called "direction sense".

Auditory response range loudness

For small sounds, it can be felt by the human ear as long as the loudness is increased slightly, but when the sound loudness is increased to a certain value, even if there is a large increase, the human ear feels no significant change. We call this auditory characteristic of the human ear's acoustical soundness a "logarithmic" characteristic. In addition, human ears have different hearing loudness for sounds of different frequencies. For example, if we play a sinusoidal AC signal with the same gain gradually increasing from 20Hz to 20kHz, we will find that although the gain is the same in each frequency band, the sound level we hear is not the same. In the entire audible sound frequency range of 20Hz to 20kHz, the upper and lower limit frequencies are a total of 10 octaves. As shown in the table:

Octave frequency range

Frequency range (Hz)

1 20 40

2 40 80

3 80 160

4 160 320

5 320 640

6 640 1280

7 1280 2500

8 2500 5000

9 5000 10000

10 10000 20000

We divided the audible sound into 3 parts according to the octave relationship, and determined the low, middle, and high audio segments.

which is:

Bass frequency range 20Hz 160Hz (3 times frequency)

Mid-band 160Hz 2500Hz (4 times frequency)

Treble band 2500Hz 20,000Hz (3 times frequency)

The human ear has a relatively loud sound on the mid-band, and it is relatively flat. The vocal loudness experienced by the high-frequency section gradually decreases with the increase of the frequency, and it is a slash. The bass frequency band weakens sharply below 80Hz, and the slope is steeper. We call the drastic weakening of the low-frequency band a phenomenon called "bluntness" at low frequencies.

If we invert these equal loudness curves at a certain sound level, we will get the relative frequency response diagram of all sounds in the entire frequency range of the human ear on this curve. The lower curve is inverted, indicating a lack of frequency response in the human ear at low sound levels. In contrast, inverting the upper curve of higher sound intensity achieves a flatter frequency response. The 1000Hz curve is usually used as a reference point. For high and low frequencies, the human ear's auditory response is always insufficient at low sound intensities. But the human ear is particularly sensitive to frequency bands around 300 to 6000 Hz. This happens to be the frequency range that contains the sounds of most people's speech patterns and the tones of babies crying.

Auditory response range

The human ear is not sensitive to changes in tone when the sound is low, and it is difficult to feel the increase or attenuation of the small and high ranges. With the increase of the loudness of the sound, the change of the human ear to the tone is greatly enhanced. We call this auditory characteristic of the human ear to the tone an "exponential" characteristic.

In order to compensate for this characteristic of the human ear, and to make it as balanced as possible, the volume potentiometer is usually controlled by the exponential method (Z), and the tone is controlled by the logarithmic method (D). And in the case of low loudness, a bass boost circuit (equal loudness circuit) is added to compensate for the dullness of the human ear to the bass frequency band.

Auditory response range

The human ear is very sensitive to the auditory response to the timbre, and has strong memory and discrimination capabilities. For example:

memory

When an acquaintance talks to you, you will know who is talking to you even if you have not seen him or her. You can even recognize the walking sounds of acquaintances. This shows that the human ear has a strong memory of the sounds often heard.

Resolution

Those who are familiar with musical instruments can quickly point out which instrument is played as long as they hear the sound of music. As far as Chinese stringed instruments are concerned, there are stringed and plucked instruments, such as erhu, Jinghu, Banhu, coconut nut, matouqin, etc .; plucked instruments include guzheng, guqin, sanxian, pipa, liuqin, Yueqin and so on. Even when playing in the same frequency band, you can still tell which kind of string instrument is played. This shows that each instrument has its own unique tone, and the human ear is very capable of resolving various tones.

timbre

It refers to a special auditory comprehensive feeling of the human ear on the tone, which is the sense of depth, direction, distance, positioning, reflection, diffraction, diffusion, sound in the sound field (whether it is a free sound field or a reverberant sound field), A combination of directivity and texture. Even if the world's most advanced electronic synthesizer is used to simulate a variety of instruments, such as trumpet, piano or other instruments, although the spectrum and sound can be exactly the same, it can still be clearly understood by musicians or senior audiophiles. Distinguished. This shows that although the spectrum and tone are the same, the complex tone is not the same, so that the human ear hears different music effects. This also shows that the timbre sensation is a complex and comprehensive auditory characteristic unique to the human ear, which cannot be simulated.

(4) Focusing effect

Anyone who has seen three-dimensional drawings knows that in order to enjoy the three-dimensional effect of three-dimensional flat drawings, their eyes must be defocused. The three-dimensional effect of the three-dimensional picture we see is actually a layered sense caused by the forward and backward displacement of the focal point. The human ear, on the other hand, can focus on a certain point from many sounds. For example, when we listen to the symphony, we concentrate our energy and hearing on the sound played by the violin, and the sound of music played by other instruments will be suppressed by the cerebral cortex, so that what you hear is a simple violin performance. For another example, when you read a book in a bustling bazaar, when you focus on books, you will not hear the noise of the bazaar. This kind of suppression ability varies from person to person, and people who often do hearing exercises have a stronger suppression ability. We call this hearing characteristic of the human ear the "focus effect". Doing more exercises in this area can improve the human ear's ability to distinguish the tone color, quality, resolution and level of a certain spectrum.

After understanding and mastering the above characteristics of human ear hearing, you can make full use of these characteristics, strengthen the absorption of the sound quality of various musical instruments and the various playing skills of musicians, and continuously improve the ability of music appreciation.

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