Monaural Phase Effect: Cancellation and Reinforcement of Distortion Products f2−f1 and 2f1−f2

Abstract

When two primary tones in the frequency ratio f1:f2 = 2:3 are presented to human listeners, a combination tone is audible at f1/2. The loudness of this combination tone depends on the phase angle between the two primary tones. We measured the amplitude and phase of the combination tone using a cancellation- plus probe-tone technique. The phase effect can be explained by interaction of a second-order distortion product f2−f1 and a third-order distortion product 2f1−f2 of approximately equal intensities. The intensity relative to the primary tones of both distortion products is influenced strongly by frequency of the primary tones and weakly by intensity of the primary tones.