Noise meter can be divided into those categories
.From the measurement object, it can be divided into the characteristic measurement of environmental noise (sound field) and the measurement of sound source characteristics.
2. From the time characteristics of the sound source or sound field, it can be divided into steady-state noise measurement and unsteady-state noise measurement. Non-stationary noise can be divided into periodic noise, irregular noise and pulse sound.
3. From the frequency characteristics of the sound source or sound field, it can be divided into broadband noise, narrowband noise and noise containing prominent pure tone components.
4. From the accuracy of measurement requirements, it can be divided into precision measurement, engineering measurement and noise census.
