Tinnitus masker closely matched to the pitch and spectrum of the tinnitus, and as loud or somewhat louder than the perceived loudness of the tinnitus. The trigger sound is applied to the ear or ears with tinnitus and typically lasts a minute or two. Not everyone can experience RI; for those who do not, tinnitus masking is likely to be ineffective. Two qualities of a tinnitus masker need to be taken into account: how effective the masking is, and how intrusive or distracting the generated sound itself is. The masking sound may have various temporal, spectral and amplitudinal characteristics. In some cases,
Tinnitus masker amplitude determines the degree of masking achieved. In some cases, the required masking amplitude is so high as to cause discomfort to the user of the sound generator, and the tinnitus is therefore considered unmaskable. The frequency and other characteristics of tinnitus can vary over time, and the shifts can be temporary or permanent. They may also be cyclical. Therefore the optimal tinnitus mask may need to be adjusted periodically, within days, hours, or even minutes. So a fixed recording (i.e. CD, DVD or audio file) of a tinnitus mask is not a very efficacious application. There are also safety