Effect of spectral resolution on the intelligibility of ideal binary masked speech

Most binary-mask studies assume a fine time-frequency representation of the signal that may not be available in some applications (e.g., cochlear implants). This study assesses the effect of spectral resolution on intelligibility of ideal-binary masked speech. In Experiment 1, speech corrupted in noise at -5 to 5 dB signal-to-noise ratio (SNR) was filtered into 6-32 channels and synthesized using the ideal binary mask. Results with normal-hearing listeners indicated substantial improvements in intelligibility with 24-32 channels, particularly in -5 dB SNR. Results from Experiment 2 indicated that having access to the ideal binary mask in the F1/F2 region is sufficient for good performance.