In the final part of a 9-part course on modeling pressure acoustics in COMSOL Multiphysics®, we turn our focus to solving large, transient pressure acoustics models using the time-explicit method. We give a detailed explanation regarding the application areas and use cases for where this method should be considered or can be applied. A modified version of the model simulating the acoustics of a room is used to demonstrate adding and using the Pressure Acoustics, Time Explicit physics interface.