Public places need some acoustic treatment to have a clear voice environment; commercial places and manufacturers need to control their own noise to avoid invading surrounding residents; HIFI enthusiasts need good sound insulation and high-fidelity sound field to create the sound of sound; music People and recording engineers also face various acoustic problems and need a more accurate listening environment. Solving the noise problem and providing efficient products and solutions for home theater construction has laid a solid foundation for perfect audio-visual entertainment.
Physical characteristics of noise
Noise is the sound produced by the sound source as a random and non-periodic vibration. From an environmental point of view, noise refers to sounds that people don't need, are disgusting, or have a hindrance to human life and work.
The size of the sound is related to the "sound pressure". The sharpness or sinking of the sound is related to the "audio" level. Whether the sound is pleasing or noisy is related to whether the "tone" is harmonious.
(1) Audio audio is the frequency of sound. A vibrating object, the number of vibrations per second is the vibration frequency of the object, and the unit of frequency is Hertz. Generally speaking, a wave with a vibration frequency between 20 Hz and 20,000 Hz is audible, so it is called a sound wave, and the source of the sound wave is called a sound source. Below 20 Hz and above 20,000 Hz are in the range of infrasound and ultrasound, respectively, which cannot be heard by the human ear. In the range of sound waves, the pitch changes from low to high as the frequency increases, but the sensation of the human ear is not consistent in different frequency bands. Under normal circumstances, the audio is below 1000 Hz, and as the frequency decreases, the hearing will gradually become dull. Therefore, the human ear is more susceptible to low frequency noise, while the high frequency noise is more sensitive and poorly tolerated. If you live in a high-frequency environment with high frequency for a long time, it will cause partial or severe deafness in the ear.
(2) Sound pressure sound can be transmitted in the air because the vibration of the object causes local pressure change of the surrounding air. This pressure change causes local density change of the surrounding air, and the local density change causes the air pressure of the far part. Change, and so on, will pass this pressure change to a farther part, thus causing the spread of sound. In the process of sound propagation, the pressure change of the air pressure with respect to atmospheric pressure is called sound pressure, and its unit is Pa (Pa). Scientists generally use the inverse pressure logarithm as the expression unit, that is, the sound pressure level is used to express the volume of sound. The unit of sound pressure level is decibel. We hear the bottom sound in our daily life, and the sound pressure level is around 0-140 decibels. The intensity of the noise is also expressed in terms of sound pressure levels.
Noise measurement and impact
The minimum sound level that a normal person can feel is 1 decibel. The soft whisper is about 30 decibels. The conversational language is about 60 decibels at a distance of about 1 meter. The bus is about 80 decibels. The noise in heavy-duty trucks, weaving workshops and subways is about 100 decibels. The sound pressure level limit for earache is called the ear valve, and the value is 120 decibels. The cannon roared and the jet took off about 130 decibels.
Noise level of 30 to 35 decibels is a relatively quiet and normal environment; more than 35 decibels will affect sleep and rest; more than 50 decibels interfere with conversation, causing distraction, lack of concentration; long-term work or living in a noise environment above 90 decibels It can seriously affect hearing and other diseases such as cardiovascular diseases. At the same time, noise also has a psychological effect. Under high-frequency noise, most people are anxious and prone to excitement.
Tips for home noise reduction
The audio-visual company is dedicated to providing customers with a variety of professional-grade soundproof windows, doors and soundproofing materials. In addition, people can also choose to make small changes in small places such as furniture and accessories, so as to eliminate the noise effect to a greater extent.
Wall walls should not be too smooth. If the wall is too smooth, the sound will echo when it touches a smooth wall, increasing the volume of the noise. Therefore, it is possible to use a decorative material such as a wallpaper that has a good sound absorbing effect. In addition, a decorative material such as a cultural stone can be used to roughen the surface of the wall, so that the sound wave is repeatedly refracted, thereby weakening the noise.
Wooden furniture absorbs noise with wooden furniture. The wooden house has the characteristics of fiber porosity and can absorb noise. At the same time, more furniture should be purchased. If the furniture is too small, the sound will resonate indoors and increase the noise.
Fabric decorative fabrics also have a good sound-absorbing effect. The drape and tiled fabrics have the same sound absorption and effect, such as curtains, carpets, etc., among which the sound insulation of curtains is most obvious. It is a good choice for both sound absorption and good decorative effects.
Round Series Sensor Automatic Dustbin
Stainless Steel Garbage Can,Round Series Sensor Automatic Dustbin,Round Series Sensor Dustbin,Round Series Automatical Indoor Dustbin
NINGBO ZIXING ELECTRONIC CO.,LTD. , https://www.zixingautobin.com