# 1/3 octave A-weighted acoustic noise spectrum (plot_ASWL_13oct)

Post-processing documentation
Matlab commandplot_ASWL_13oct
Module AC.pp
Description PLOT_ASWL_13oct plots the A-weighted acoustic noise spectrum in one third octave
Parameters
Restrictions

### Description

This particular post-processing allows to visualize the Sound Power Level (SPL) in an other way than plot_SWL_fft. The A-weighted acoustic noise spectrum in one third octave visualization is often prefered by acousticians because it takes into account the human’s ear physiology.

In fact, the A-weighting, defined by IEC 61672-1:2013, is established to take into account the average sensitivity of human’s normal audition for each range of frequencies (in octave or third octave). For example, as the ear is less sensitive to low frequencies, the A-weighting will give to it less weight. Several acoustic weighting also exist for several applications, as the B,C and D-weightings.

### Result

1/3 octave A-weighted sound power level spectrum
plot_ASWL_13oct