White noise is noise whose amplitude is constant throughout the audible frequency range. The sound of white noise is a high-pitched hissing, similar to the sound of steam escaping from an overheated radiator. White noise is produced by a random noise generator, and is used in tinnitus maskers and in Tinnitus Retraining Therapy. More technically, white noise is defined as sound with equal power per Hz in frequency. Since each successive octave of frequency has twice as many Hz in its range, the power in white noise increases by a factor of two for each succeeding higher octave. Thus, white noise increases by 3 dB per octave in power. Incidentally, our ears hears the high frequency hissing in white noise more than the lower-frequency sounds since the ear is more sensitive to high frequencies. This high-frequency sound tends to grate on the nerves more than lower frequency sounds, so now they are beginning to use the more natural-sounding pink noise in tinnitus maskers and related devices instead of white noise.