Influence of bichord interval on perception of simultaneity

The present paper describes the influence on perceptual simultaneity of the bichord interval between two pure tones. In the experiment, 50 participants (musicians and nonmusicians) listened to tone pairs (bichords: C-D, C-E FLAT: C-F SHARP; C-G) with different degrees of asynchronization and indicated whether two tones had been simultaneous or successive. The method of constant stimuli was used. An analysis of variance showed that bichords' intervals were perceived with different degrees of simultaneity. Tones less distant in frequency were not necessarily easier to perceive as simultaneous. This result suggests that judgement of simultaneity cannot be accounted for only in terms of frequency or temporal relationship between single stimuli at the physical level. The effect of a nontemporal variable concerning the perceptual moment hypothesis is discussed.