Ansys Employee
It is not clear what is your final goal. Do you want to plot the contours of the sound waves in the simulation domain? - On the FWH surfaces? - Outside the simulation domain?
With the FWH model you can plot and analyze the surface pressure levels on the selected FWH surfaces, as described in the User's guide "23.2.6. FFT of Acoustic Sources: Band Analysis and Export of Surface Pressure Spectra". Also you can plot (directly in Fluent) the Surface dpdt RMS on acoustic sources that are defined as walls. Moreover, you can use the model to compute the pressure signal to one or more receiver locations and then use the FFT tool to obtain a local spectra.
If you are planning to visualize the sound waves inside your domain (on any cut plane of your choice) then it all depends on the simulation settings. If it is a compressible fluid simulation then you can visualize the contours of static pressure (hydrodynamic + acoustic pressure).
Hope this helps