Predicting echo thresholds from speech onset characteristics.

Echo threshold variability has previously been examined using stimuli that are carefully controlled and artificial (e.g., clicks and noise bursts), while studies using speech stimuli have only reported average thresholds. To begin to understand how echo thresholds might vary among speech sounds, four syllables were selected in pairs that contrasted abruptness vs gradualness of onset envelopes. Fusion and discrimination suppression thresholds, two echo thresholds commonly used to study the precedence effect, differed among syllables. Results were used to evaluate two predictive heuristics adapted from perceptual center (p-center) models.