Sound Simulation

Hi ! I'm a graduate student and doing my project in unity. My project is sound simulation in streets. I have simulated the sound and scripted where the sound is simulated in a box which i created (i.e. cell) but I can't make the sound particle to hit the building and make it bounds back. I can provide you the entire script, I need to make the sound particle to bounds on the building. Can you hep me with this? sound is simulated in relationship to audio. I want to make the object as an input for the particles to get attracted.