Interrupted noise as a tinnitus masker: an annoyance study.

Tinnitus can be masked by a simultaneous and/or nonsimultaneous stimuli. The usefulness of the masker depends on its power and its perceived annoyance. The purpose of the current study was to compare annoyance produced by interrupted and continuous noises. Data were gathered from six normal-hearing subjects without tinnitus and six subjects with tinnitus. Continuous white noise and interrupted white noise (2, 4, 10, 20, and 40 pulses per second) were presented at 20, 40, and 60 dB. Subjects adjusted the interrupted noise to be as annoying as the reference signal. The general findings were: (1) interrupted noises were more annoying than the continuous noises for both groups, and (2) the perception of annoyance in both groups was very similar at the highest level and significantly different at lower levels. For normal-hearing listeners, the differences between annoyance produced by continuous and interrupted noise were independent of the pulse rate for rates slower than 10 pulses per second, gradually decreasing for the higher rates. Despite the advantages of interrupted noise, it is not suitable as a tinnitus masker since it is more annoying than continuous noise.