Head Shadow Effect

Head Shadow Effect

The sensation of sound comes from our ability to distinguish the source of the sound based on the variation in the volume of sound perceived between both our ears. This phenomenon is known as the Head Shadow Effect.

Lower frequency sounds tend to have longer wavelengths and range up to 1000Hz. Due to this, one can recognize the source of these sounds as a result of the timing difference between both ears which ranges from about 0.2 to 0.8 milliseconds.

Higher frequency sounds above 1000Hz have shorter wavelengths which tend to get blocked due to the diameter of our heads which is about 8 inches. The ear which is located nearest to the source of the sound is known as the leading ear whereas the other ear is known as the lagging ear. The difference between the volumes perceived by both ears enables us to locate the source of the sounds which is why emergency vehicles tend to have high pitched sirens.

Head Shadow Effect also affects armed soldiers engaged in combat. The leading ear is closest to the barrel of their rifle which perceives more volume that can result in higher chances of hearing loss in that ear compared to the lagging ear. This means that right handed soldiers are most likely to sustain hearing loss in their left ear since they tilt their heads while using the rifle, exposing their left ear to hearing damage.

People who have difficulty in locating the source of sounds as a result of hearing loss are unable to successfully use the Head Shadow Effect that can help them locate the source of various types of higher frequency sounds. Learn more about the Head Shadow Effect and how its deterioration could be affecting you or a loved one and contributing to hearing loss.