Characteristics of sound

From the concept of sound, sound is a physical phenomenon. So sound generally has four physical characteristics: pitch, intensity, length and quality.

1, pitch

Pitch refers to the level of sound. It is determined by the number of times the pronunciation body vibrates per unit time, that is, the frequency. The higher the frequency, the higher the sound; Low frequency, low voice.

The unit of calculation of frequency is called hertz, and one vibration per second is one hertz. The range of sound that normal people can hear is about 16 to 20000Hz. Infrasound is below 16 Hz, and ultrasonic is above 20000Hz. The vibration frequency of the sounding body is determined by the starting point of the sounding body. Generally, large, thick, long and loose objects vibrate slowly, so the sound is low. Small, thin, thin, short and tight objects vibrate quickly and have high sound.

2. Sound intensity

Sound intensity refers to the strength of sound. Is determined by the vibration amplitude of the pronunciation body, that is, the amplitude. The greater the amplitude, the stronger the sound; The smaller the amplitude, the weaker the sound.

The amplitude is calculated in decibels (bB). Generally speaking, the intensity of ordinary conversation is around 60-70(bB). If it is as high as 120- 130(bB), many people will feel that the sound is too loud and their ears hurt. Below 40(bB), others can't hear you clearly.

3. Sound length

Sound length refers to the length of sound. It is determined by the duration of the vibration of the object when it is pronounced. The longer the pronunciation body vibrates, the longer the sound will be, otherwise it will be shorter.

The unit of sound length is milliseconds (ms). Generally speaking, the sound length is not the main means to distinguish meaning in Chinese, but a natural attribute of pronunciation, and it often appears as an accompanying feature.

4, timbre

Timbre, also known as timbre, refers to the characteristics and essential features of sound, which is the most fundamental feature that distinguishes a sound from other sounds. It is determined by the formation of sound waves, and the sound quality is different with different waveforms.