The threshold of a 1000‐Hz sinusoidal signal masked by two or four tones placed symmetrically around the signal was investigated as a function of the frequency difference (ΔF) between consecutive maskers as well as masker level. The results concur with previous evidence that (1) the masked threshold decreases linearly as ΔFincreases for a two‐tone masker, and (2) the difference between masked thresholds is much greater than would be predicted on the basis of a simple summation of masking power or intensity. For small ΔF, the size of the difference (6–8.5 dB) did not vary greatly as level changed. At larger frequency separations, the highest levels produced more difference than lower levels. It was concluded that the difference between two‐ and four‐tone masking was (1) dependent upon the level of the maskers and the frequency separation between the maskers, and (2) independent of the masking contributed by the individual maskers.