How loud is 25 decibels, and what is 25 decibels

How loud is 25dba or what does it look like Here's a table for you:

Compare one by yourself.

130 decibels.

The propeller plane took off, and the loudest screams of the people were louder.

120 dB ball mill.

Job. The above sound will cause tinnitus.

110 dB chainsaw work, general home audio equipment maximum volume.

100 dB The tractor starts.

90 dB Very noisy road.

The above sounds affect hearing.

60 80 dB for general vehicle driving.

70 dB Speak loudly, the upper limit of comfort (louder than this one is noisy) 40 60 dB Speak in general.

50-53 dB: the sound of the washing machine.

50 dB office.

40 dB Library, Reading Room (Beyond this sound will affect sleep) 30 dB Bedroom, desert night.

20 dB Whisper softly, country night.

15 decibels: The sound of a pin falling from a height of 1 centimeter from a distance of 1 meter.

13 dB The hum of a light bulb.

10 dB The wind rustles the leaves, very quiet room.

0 dB Just after the hearing is aroused, a mosquito is flying 10 feet (about 3 meters) away.

Hope this helps.

The sound of 25 decibels is very small, and it is generally believed that we can hardly hear sound waves below 20 decibels, and only sound above 20 decibels can be heard.

25 decibels is equivalent to the volume of two people's whispers.

Decibel is a unit of measurement that measures the ratio of two quantities of the same unit, mainly used to measure the intensity of sound, and is often expressed in DB. A decibel represents a unit, i.e., the ratio of two electrical or acoustic powers or the ratio of two voltage or current values or similar sound volumes; Decibel is also a unit of measurement of the relative loudness of sound.

1. A unit that expresses the ratio of power to energy, which is equal to 10 times the commonly used logarithm of the ratio of power intensity.

2. A unit that expresses the ratio of field quantities, equal to 20 times the commonly used logarithm of the ratio of field strength amplitude.

3. The unit of sound pressure level is approximately equal to the minimum graduation value of the loudness difference that can be detected by the human ear.

Decibels were originally used in long-distance telecommunications, and have since been widely used in electrical, radio, mechanical, shock and vibration, mechanical power and acoustics.

52 decibels is equivalent to the sound of a refrigerator vibrating.

A noise level of 30 to 40 dB is a relatively quiet normal environment; Anything above 50 decibels can affect sleep and rest. Due to insufficient rest, fatigue cannot be eliminated, and normal physiological functions will be affected to a certain extent; More than 70 decibels interfere with conversation, causing upset, lack of concentration, affecting work efficiency, and even accidents; Long-term work or living in a noise environment above 90 decibels can seriously affect hearing and lead to the occurrence of other diseases.

45 decibels. Between 40 and 60 decibels, it is a normal conversation sound. When the regional environmental noise of the community reaches the noise environmental quality class 1 standard, it is suitable for human habitation, that is, it is lower than 55 decibels during the day and 45 decibels at night, so 45 decibels is a relatively quiet sound.

The unit of sound is decibels, when the sound is loud to a certain decibels, it becomes noise, noise in life is very harmful, it will cause people to be irritable, and it will endanger people's health when it is serious.

According to normal human hearing:

0-20 dB, very quiet, almost invisible;

20-40 decibels, quiet, like a whisper;

40-60 dB, normal, normal indoor conversation;

60-70 decibels, noisy, nerve-damaging;

70-90 decibels, very noisy, nerve cells.

be sabotaged; 90-100 decibels, increased noise, hearing loss;

100-120 decibels, unbearable, staying for a minute can temporarily cause deafness;

Above 120 decibels: extremely deaf or totally deaf.

noise, predisposing to cardiovascular disease.

55 decibels, which can have a negative impact on children's learning; 60 decibels, wake people up from sleep; 70 decibels, myocardial infarction.

increased incidence by about 30%; Exceeding 110 dB can lead to permanent hearing damage.

1 dB: Just audible sound.

Below 15 decibels: Feels quiet.

30 decibels: The volume of the whisper.

40 decibels: The hum of the refrigerator.

60 dB: The sound of normal conversation.

70 decibels: equivalent to walking in the downtown area.

85 decibels: cars on the road.

95 dB: Motorcycle start sound.

Expand. Sound is actually a rapid change in pressure transmitted through the medium. When sound is transmitted in the air, the atmospheric pressure changes in cycles. The number of times the pressure changes in each second is called the frequency, and it is measured in hertz.

hz), which is defined as the number of cycles per second.

The higher the frequency, the higher the pitch of the sound. As shown in the graph below, the frequency of drumming is much lower than that of blowing a whistle. Click the [Demonstration] button to listen to the sound they make and to see the difference in tone.

Loudness and decibel scale.

Loudness is another characteristic of sound or noise. Weak noises usually have a large pressure change, while weak noises have less pressure changes. Pressure and change in pressure are measured in the form of bascal.

Abbreviated as PA. It is defined as Newton.

square meters ( n m2).

The human ear can sense sound pressure in a wide range. The faintest sound that can be heard by the normal human ear is called the hearing and annihilation threshold, which is a pressure change of 20 microbascas (abbreviated as PA), which is 20x10-6 pa"Twenty parts per million Bascal")。On the other hand, a very noisy situation can produce a large pressure change, such as a space shuttle.

At maximum horsepower, it produces a noise of approximately 2,000 pa or 2 x 109 pa at close range. The table below shows the different sound pressure levels resulting from the above conditions.

Expressed in Basca and microbascara. If the Pa is used to express sound or noise, we have to deal with numbers as small as 20 and as large as 2,000,000,000.

Obviously, it is quite inconvenient to use the word Pa to express sound or noise. An easier way to do this is to use a logarithm.

The logarithmic scale is used to express the loudness of a sound or noise, based on 10.

To avoid using Pascal (Pa) to express sound or noise (in case of dealing with numbers that are difficult to manipulate), the decibel (dB) scale is used. The scale is based on the auditory threshold, 20 Pa or 20 x 10-6 Pa as the reference sound pressure value, and defines this sound pressure level as 0 decibels (dB).

Sound pressure level, usually abbreviated as SPL or LP, is measured in decibels (dB).

Generally, the sound of 50 decibels is similar to the sound of indoor chat.

Generally 20-40 decibels is about a whisper in the ear; 40-60 decibels is a normal conversation sound; More than 60 decibels belong to the noisy range; 70 decibels is noisy and begins to damage the hearing nerve; Above 90 decibels can cause hearing damage.

If you stay in a space of 100-120 decibels, you will usually become temporarily deaf (deaf) in one minute. Usually car noise is 80-100 decibels, taking a car emitting 90 decibels of noise as an example, 81 decibels of noise can still be heard at a distance of 100 meters.

Noise standards.

Noise standards are a major issue of international debate, because they are not only related to technology, but also involve huge investment, so although the "International Organization for Standardization" (ISO) recommends international standard values, many countries still publish their own standards. With the deepening of people's understanding of noise hazards and the continuous progress of science and technology, people have begun to develop from only paying attention to the impact of noise on hearing to the impact of noise on the cardiovascular system and neuro-endocrine system, so as to formulate more scientific noise standards, which is the current trend of international research on noise standards. There are three main types of noise standards.