A, B, Group mean thresholds as a function of spatial separation of the two masker talkers from the target for speech processed to retain ENV cues with speech TFS replaced with noise carriers that were either interaurally correlated over the entire frequency region (Corr TFS), uncorrelated over the entire frequency region (Uncorr TFS), uncorrelated ≥1500 Hz (HP Uncorr TFS), or uncorrelated ≤1500 Hz (LP Uncorr TFS) over 32 (A) or eight (B) frequency bands. C, D, SRM as a function of the horizontal separation of the two masker talkers from the target for the conditions shown in A and B. Thresholds and SRMs for natural speech is also shown in A and C, respectively. Error bars indicate ±1 SEM.