When selecting an in-line ducted fan, you can choose to auto-select matching silencers and immediately view the resultant sound power level.

When in the Select Fan > Advanced tab, scroll down to the Silencers panel where there are silencer options for the inlet and outlet side. You can select various combinations for comparison. For example, on the Inlet side, if you choose None and Circular 1D Open, the program will select fans with no matching silencers and fans which match a circular 1-diameter long open silencer. You can select up to 6 different inlet + outlet silencer combinations.

The Specification window will show the sound levels with the silencer(s) factored in. You will also be prompted to add any matching silencers to the schedule when adding the fan.