Wavelength (λ): the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, troughs, or zero crossings. Wavelength is inversely proportional to frequency of the wave: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.

Spatial frequency: this is the inverse of the wavelength.

Tinnitus: is a pathology characterized by the perception of a sound, often a continuous tone, when no external sound is present.

Subject: As used herein the term “subject” means any human person subjected to the treatment described herein.

Clinician: As used herein the term “clinician” means a person administering the treatment described herein, and does not imply any particular degree of medical training.

Sine cluster: as used herein a “sine cluster” refers to a group of three or more sine waves of similar amplitude but varying frequency comprising at least a base frequency sine wave, a sine wave with a frequency n % above the base frequency, and a sine wave with a frequency n % below the base frequency. Other frequencies evenly spaced apart from the base frequency may additionally be included. Rather than indicate a percentage difference, we may also refer to a difference in frequency of a certain number of degrees. Note that in other embodiments, the waveforms may not be sine waves, but may be square-shaped, saw-shaped etc. So when we refer to a sine-wave cluster it is implied that we may also be describing waves having other shapes. In use, the amplitudes may vary up to whatever level the audio technician decides, but amplitude is generally not varied significantly.