Wideband monaural envelope correlation perception.

This study investigated monaural envelope correlation perception (Richards 1987) for noise bandwidths ranging from 25 to 1,600 Hz. The high-frequency side of the low band was fixed at 3,000 Hz and the low-frequency side of the high band was fixed at 3,500 Hz. When comodulated, the magnitude spectra of the pair of noise bands were either identical or reflected around the midpoint. Six listeners with normal hearing participated. Listeners showed similar performance for identical and reflected-spectrum conditions, with best performance usually occurring for bandwidths between 200 and 800 Hz. Results were considered in terms of envelope comparisons of waveforms at the outputs of multiple peripheral filters or envelope comparisons of waveforms at the outputs of central filters set to the bandwidths of the noise stimuli. Some aspects of the results were incompatible with the account based on multiple peripheral filters. However, the results of a supplementary condition involving the gating of band subregions indicated that this incompatibility could be accounted for by nonoptimal weighting of peripheral filter outputs.