Several Typical Sound Level Meters are Introduced
1. Integral sound level meter - it can directly display the equivalent continuous sound level of the measured noise within a certain measurement time in digital form. For unsteady noise, it is required to measure the equivalent continuous sound level Leq of the noise, which is defined as: at a certain point in the sound field, use the method of energy averaging within a certain period of time to combine several different A sound levels that change intermittently , using an A sound level to represent the noise level during this period.
2. Digital sound level meter - a sound level meter that displays measurement results digitally. It not only has the advantages of intuitive and accurate readings, but also can be processed with other analysis and processing instruments and computers through BCD code output.
3. Impulse sound level meter - measure the effective value of the measured signal through the pulsation characteristics of the capacitance at different times, and has a high peak factor capacity, so it can respond to the pulse sound with a short duration and a low repetition ratio . In life, we often encounter discontinuous noise, that is, pulse sound or impact sound, such as typewriter noise, stamping machine noise, guns and so on. This noise is short-lived, may recur for a long time, or even occur only once in a period of time. If it is measured with a general sound level meter, there will be a large error, so a pulse sound level meter should be used.
4. Environmental automatic monitoring (noise statistics, spectrum) analyzer - can automatically collect and calculate noise data according to preset functions, and directly display the results (and store the data at the same time).
Classification of sound level meters
1. According to the purpose, it can be divided into general sound level meter, integral sound level meter, automatic monitoring (statistics, spectrum) sound level meter, etc.
2. According to the accuracy, it can be divided into type 2 (allowable error 1 d B) and type 1 (allowable error 0.7 d B) sound level meters.
3. According to the volume, it can also be divided into desktop, portable and pocket sound level meters.
4. According to its indication method, it can be divided into analog indication (pointer type) and digital indication sound level meter.
