The head creates a "sound shadow" by partially blocking transmission of the sound. When this occurs, the sound reaching the far ear has a reduced intensity. The impact of the sound shadow systematically varies with the spatial location of the sound, so interaural intensity differences may provide important information for auditory localization. This demonstration illustrates the interaural level difference cue for spatial localization. Position your head in between your computer's speakers. Listen to each tone and note its perceived spatial location. You can also try this with stereo headphones.
In the second presentation, when the sound comes mostly from the right speaker, why specifically do you perceive the source of the sound as coming from your right?
a. Because the sound that reaches your right ear is more intense than that reaching your left ear.
b. Because the sound that reaches your right ear is less intense than that reaching your right ear.
c. Because the sound reaches your left ear sooner than it reaches your left ear.
d. Because the "sound shadow" makes the sound reach your right ear sooner than your left ear.