This study investigated the effects of 4 band widths of noise of different center frequencies presented at three sensation levels on the size of the differential threshold (ΔI) for intensity. Eleven untrained subjects and three trained subjects served in a study employing the method of limits. Analysis of the data showed that ΔI's for a low octave band (127–225 cps) of noise were larger than those for a middle octave band (1040–2080 cps) and high octave band (4080–8160 cps) of noise. The middle and high bands in turn yielded ΔI's that were larger than those for a wide‐band noise. The magnitude of the ΔI's for the octave noise bands were tentatively related to the average ΔIfor those frequencies contained in the band. Comparison of the ΔI's for wide‐band noise to those obtained by other experimenters showed close agreement.