Some considerations for the design of auditory displays

Two experiments evaluate the effect of noise on the accuracy of sound localization judgments, with an eye toward the environments where 3-dimensional auditory displays are likely to be implemented. The ability to determine whether a sound came from the front or from the back and whether a sound came from above or from below is disrupted at much higher signal-to-noise ratios than the ability to determine whether a sound came from the left or from the right. Changes in the location of the masker can have complex effects on the pattern of localization errors. A third experiment examined the ability to localize speech signals, as might often be required in auditory displays. The results also indicate that the ability to distinguish front from back and up from down is easily disrupted (i.e., it is worse for speech than for nonspeech signals), but that the ability to determine left from right is robust (i.e., it is similar for speech and for nonspeech).