Introduction to Sound Level Meters
Sound level meter is a kind of instrument to measure sound pressure level and sound level according to certain frequency weighting and time weighting. It is the most commonly used instrument in acoustic measurements, can be industrial noise, traffic noise, environmental noise and living noise, etc., according to the human ear hearing characteristics of the approximate determination of its noise level instrument.
Sound level meter can be applied to environmental noise, electromechanical product noise, traffic noise, building acoustics and electroacoustics measurements. Some sound level meters can also be used to measure vibration by replacing the receiver section. The external connection or internal setting of octave filter or 1/3-octave filter of the sound level meter can be used for the spectrum analysis of noise.
With the development of electronic technology, especially large-scale integrated circuits and computer technology, the frequency counter, detector and filter circuits in the sound level meter are realised by digital signal processing technology instead of analogue circuits. This not only makes the circuit more simplified, wider dynamic range, but also greatly improve the function and stability, especially real-time spectrum analysis can be achieved, so that the sound level meter is more widely used.
The sound level meter consists of microphone, attenuator, weighting network, amplifier, detection network and indicator. The foremost part of the sound level meter is the microphone, which converts the sound energy into electrical energy and sends it to the preamplifier of the host computer, amplifies it and sends it to the attenuator and the weighting network, and then finally displays the sound level reading through the detector and the indicator table with certain damping characteristics.
