FIGURE 1.

Schematic of testing configuration and stimulus rhythms. The listener was seated in an anechoic chamber in the center of a horizontal array of small loudspeakers that were positioned at 5 or 10° intervals. The target source (denoted by red) was fixed at 0°, and the masker source location (blue) was varied parametrically in azimuth (i.e., the horizontal dimension). In the 40° target condition, the listener was turned to face 40° left, placing the target 40° to his/her right. Stimulus Rhythm 1 or 2 consisted of a sequence of noise bursts (denoted by red bars) that were interleaved with masker noise bursts (blue). The vertical offset of blue bars in the illustration indicates that target and masker sources could differ in azimuth.