SOUND LEVEL MEASUREMENT
A sound level meter is used for acoustic (sound that travels through air) measurements. ... The diaphragm of the microphone responds to changes in air pressure caused by sound waves. That is why the instrument is sometimes referred to as a Sound Pressure Level (SPL) Meter.Sound waves in air are longitudinal waves.
The sound level meter is a measuring instrument used to measure sound pressure level. The disturbance that propagates in air is a change in the local air pressure.The speed of sound in air depends on several factors, including the air temperature and pressure. At room temperature and standard atmospheric pressure, the speed of sound is 343 m/s.A dynamic microphone takes advantage of electromagnet effects. When a magnet moves past a wire (or coil of wire), the magnet induces current to flow in the wire. In a ribbon microphone, a thin ribbon is suspended in a magnetic field. Sound waves move the ribbon which changes the current flowing through it.