According to one embodiment, a method, computer system, and computer program product for modulating external sounds to reflect the acoustic effects of virtual objects in a mixed-reality environment is provided. The present invention may include creating a knowledge corpus, recording a sound effect occurring externally to a mixed-reality environment experienced by a user operating the mixed-reality device; identifying one or more objects within the mixed-reality environment, including at least one virtual object; modulating the sound effect based on the knowledge corpus to simulate one or more acoustic effects of the one or more objects within the MR environment; and playing the modulated sound effect to the user.