A simple extension of the Webster‐Jeffress model of the BMLD is presented with its predictions for (1) the effects of various stimulus parameters on the size of the BMLD, (2) the relative size of the BMLD in simultaneous and post‐masking, and (3) the dependence of the BMLD on differences in frequency between the signal and masker. Data illustrate the high correlation between observers' sensitivity to level differences and their sensitivity to interaural delay. The attentuation characteristic of the interaural‐delay‐tuned mechanisms responsible for the BMLD is also illustrated.