果拼音等响曲线（Loudness curve）
什么汤有营养
After a lot of experimental measured loudness, such as curve of pure tone as shown in figure loudness curve - auditory threshold curve, it express the pure tone of the typical listener think same loudness of sound pressure level and frequency, the relationship between ordinate is sound pressure level in the figure, the abscissa is frequency, they are the objective physical quantity of sound.
可乐土豆饼
Becau the frequency is not at the same time, the subjective feeling of the human ear is different, so each frequency has its own threshold sound pressure level and the pain threshold sound level, which can connect them to get the threshold line. There are thirteen loudness levels and units for the difference between the two lines.
The threshold line is zero and the pain threshold is 120. All points on the same curve, although they reprent different frequencies and sound pressure levels, their loudness is the same, so they are called equivocal curves.
The magnitude of the loudness level (square) reprented by each of the equivocal curves is determined by the sound pressure level of the curve at 1000Hz. For example, the noi sounds as loud as the ba tone of the 85dB, the noi level of the noi, which is 85 square.
Loudness curve
For pure sound, the isoclu curve indicates the relationship between loudness and frequency. Ear to different frequencies
of sound is not the same as the smell of threshold and pain threshold and nsitivity are also different. For example, 200 hz 30 db sound and 1 KHZ 10 db of loudness of voice in the ear with the same sound, this is the so-called "loudness" different frequencies, with different intensity, but they do have equal loudness level, the unit is square (phon), such as 40 or 60 square respon curve. At low intensity, the isoclines are similar to the auditory threshold. So if the intensity of the sound is equal, then the middle frequency sounds louder than the low-frequency or high-frequency sound. With the increa of loudness level or sound pressure level, the equivocal curves gradually become straight. That is to say, the loudness level of growth rate of different frequencies is different, low frequency sound loudness level along with the growth of the intensity of the sound faster than intermediate frequency sound, this shows that when strong loudly, to the human ear is nsitive to low-frequency sounds more. A composite sound consisting of a linear or continuous spectrum, generally speaking, the wider the range of frequencies it includes, the louder its sound, even though the total sound can be maintained. Studies have shown that the relationship between loudness and bandwidth is only pr
oduced when the bandwidth exceeds a minimum threshold, or critical bandwidth. In the critical bandwidth, the loudness is largely independent of the bandwidth, which is usually called the loudness synthesis, and the loudness of the sound is also associated with the duration of the sound. In a certain range (about 15 ~ 150 ms), the longer the duration, the louder the sound. Beyond that, the relationship does not exist.
林志炫身高The experiment shows that the threshold and the pain threshold are changed with the pressure and frequency. The area between
不停的赞美
the auditory threshold and the pain threshold and the frequency variation is the auditory range of the ear. Generally, for 1kHz pure sound, 0dB - 20dB is quiet, 30dB - 40dB is weak, 50dB - 70dB is normal sound, 80dB - 100dB is sound, 110dB - 130dB is the sound. For the audible sound outside of 1kHz, there are numerous equivalent sound pressure - frequency values on the same level of loudness curve, for example,
The sound of 30dB in 200Hz and 10dB in 1kHz sounds the same loudness in the ear, and this is what is known as "waiting."
Loudness curve
A curve of the sound pressure of a pure sound of the same level of sound. Abscissa, on the curve ring for the pure tone frequency, ordinate the sound pressure level needed to reach the loudness level (db), each curve reprents a loudness level. As with 40 song reprents sound loudness at various points in the curve is the same, the loudness level they are 40 song. (a)
The human auditory characteristic curve is a curve that reflects people's psychological factors of the amplitude range of the sound, which corresponds to no on each curve
The sound pressure level of the same frequency is different, but the respon of the human ear is the same, so it is called the isoclu curve and the note on each curve is
A number, which is a unit of loudness, is known by the isoclu curve family. When the volume is low, the person's ear is low and the volume is low
伍子胥的故事At large, the high bass feels full and the person is most nsitive to the sound of 1000hz-4000hz. Tian shengping, a teacher of Beijing economic and trade high technology school
In 18Hz - 18KJz audible frequency range, the listener can feel the loudness of the sound, not the amplitude of the acoustic vibrations. The loudness is related to the frequency of the sound. In the lo
w voice, the ear is most nsitive to the sound of 1-3khz in the middle frequency band, and the sound of high and low frequency bands, especially the low frequency sound, becomes dull. In addition, the loud voice signal level, the listener feel the loudness and the relationship between the frequency is not too big, the same amplitude of each frequency sound, the listener feel the loudness and the relationship between the frequency is not too big, the same amplitude of each frequency sound, sound feeling loudness. But for low grade zhiqiang signal respon, the relationship between feeling and frequency, for the same signal amplitude, the human ear was high and low frequency sound than the intermediate frequency sound, and this phenomenon is more obvious with the decrea of the amplitude of sound.天秤座和处女座
This phenomenon is called the Fletcher - munson effect. A lot of hearing people and the average, the effect of the characteristics of the resulting is the famous darren Fletcher - munson loudness curve, the curve reflects the psychological and physiological factors of the intensity of the sound to the human ear subjective feeling of the curve.
Wait for the loudness curve, which is to match the pure tone
of different frequencies with different intensities and the pure sound of 1kHz. The intensity value of a certain pure tone of 1kHz as the loudness of the other frequency on the other frequency curve.
The condition of obtaining such a curve is that the listener faces the direction of the sound source. When the listener is abnt, the sound field is the plane free traveling wave; The sound pressure level of the sound field should be measured in the abnce of the listener.
Fletcher - Munson curve. Fletcher and Munson were rearchers in the 1930s who first measured and published a ries of curves showing the nsitivity of the ear to frequency. They eventually proved that the hearing of the people was highly dependent on the loudness of the sound. The curve shows that the most nsitive area of the ear is between 3 kHz and 4 kHz, which means that the sound of 3-4 kHz or less must be amplified to be heard. Therefore, the Fletcher - Munson curve is considered to be a high level of sound.
The curves range from the "just heard" sound (0 dB SPL) to the sound of the human ear (130 dB SPL), which is usually added to the 10 dB loudness increment.
The isoclavic curve is a curve of the sound pressure of the same frequency with the same frequency. Abscissa, on the curve ring for the pure tone frequency, ordinate the sound pressure level needed to reach the loudness level (dB), each curve reprents a loudness level. As with 40 decibels reprents sound loudness at various points in the curve is the same, the loudness level
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