Additional Information
The equation to calculate L
eq divides the integrated, normalized sound pressure by the duration of interest of the signal. The result is expressed in units of decibels:
- Leq = equivalent continuous sound pressure level in dB
- p0 = reference pressure level (typically 20 µPa)
- pA = acquired sound pressure
- t1 = start time for measurement
- t2 = end time for measurement
It is important to note that the Leq calculation is performed on time domain data, so the resultant sound level does not represent any specific band of frequencies. To calculate Leq across a certain band, you must first filter the data to isolate the frequency band of interest. The example below uses the SVL Leq Sound Level.vi in conjunction with an A-weighted filter to calculate the equivalent continuous A-weighted sound pressure level of a signal:
Equivalent continuous A-weighted sound pressure level is a common measurement used in industry to characterize noise levels in loud environments. The result is expressed in dB(A), a weighted decibel scale that filters frequency components to roughly imitate the hearing profile of the human ear.