Work Step by Step
The sound waves from the two speakers interfere with each other, as predicted by the principle of superposition. The path lengths to each speaker differ for listeners at different locations scattered around the room. At some locations, the path difference will be an odd number of half wavelengths, and the received waves will destructively interfere, producing a dead spot. At other locations, the path difference will be zero or an integer number of whole wavelengths, and the received waves will constructively interfere, making that a loud spot in the room.