Head shadow gives one ear a better signal-to-noise ratio in typical listening

Evidence

Better-ear advantage — In most environmental listening situations, one of the two ears receives a sound mixture with a higher signal-to-noise ratio (SNR) than the other. Acoustic head shadow causes the SNR at the two ears to be different, unless the rare condition occurs when the signal and masker are in the same location (e.g., like someone standing in front of a stereo speaker). In this way, typical everyday listening generates a “better ear” for listening. Consider a situation where a person is looking at a talker (the signal), but a noise source (such as a fan) is on their right side. Head shadow will attenuate the highfrequency components of the noise on the left side of the body, but the level of the talker will be the same at the two ears. In this way, the right ear will have a lower (poorer) SNR than the ear on the left. This effect is quantified by subtracting the threshold at the better ear from the threshold at the poorer ear. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 1544

Categorization

• XREF: connects to: The head shadows and reflects sound to create level differences between the ears. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1433; Head shadowing and binaural hearing raise sensitivity by six decibels or more — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 644