The ear’s nonlinear mechanics can physically generate missing combination frequencies

Evidence

Camps divide according to what part of the auditory chain is responsible for phantom tones. Place theory maintains that the required partials, absent in the incident sound, are created by the mechanics of the ear, so that the missing vibrations are actually real by the time they are detected by the neural system. This is quite possible on general nonlinear mechanical principles. The presence of two frequencies may in fact generate a third frequency or even several new frequencies, which could be a difference of the two, sum of the two, twice one minus the other, and so on. — Eric J. Heller, Why You Hear What You Hear- An…, 2283

Categorization

• DEFINE: Explains place theory’s account of phantom tones as mechanically real rather than purely neural.