Psychoacoustics

Psychoacoustics is the area of physics that studies human reactions to sounds, including music and speech. Hearing consists of so much more than simply the temporal lobe of the brain and the ear; there are many complex neural interactions that lead to our responses to sound. The ear, specially the cilia of the cochlea, convert sound wavelengths into neural impulses, so different wavelengths that produce the same impulses are not differentiable to the human brain. Additionally, the human ear has a relatively small range of perceptible sounds, a range that is only made smaller with age. In addition to measuring kHz relative to sound, psychoacoustic researchers also look at sound pressure, measured in atm. Psychoacoustics also deals with sound localization and the masking effects of sound. It is amazing how little most musicians and music educators know about the physics of sound. For those of us who will never record or mix our music, this information seems irrelevant. However, if we are conducting an orchestra, for example, psychoacoustics has tremendous significance for our instrumentation, location of instruments, dynamics, and other factors. If we ever have the opportunity to record our ensembles or design rehearsal or performance spaces, psychoacoustics are incredibly important. Also, from a consumer standpoint, is is exciting to see what psychoacoustic physicists can do with recorded sound and how they can reproduce it for our ears.