Such signals can stimulate specific states of consciousness, which are automatically learned and can then be recreated from memory. As long as you are using stereo equipment, the intended effect will be achieved. Be sure your earphones are comfortable. There's noise on my tapes. They all have a hissing sound which I can only partially filter out with the Dolby switch on my stereo.
Pink sound contains all the tones the human ear can perceive.
The higher and lower portions of the sound have been adjusted so you hear the entire sound equally. This helps the mind create or select sound to complete the Hemi-Sync process. DO NOT use Dolby or other noise reduction systems as they interfere with the sophisticated Hemi-Sync process. People often regard hypnosis as a process of being led into a state of high suggestibility and relinquishing control to the hypnotist. Although similar in this regard, Hemi-Sync, with its special frequencies, assists the listener in achieving the desired state of consciousness much more quickly.