https://web.archive.org/web/20240204115156/https://www.independent.co.uk/arts-entertainment/music/features/the-music-industry-s-100-most-influential-people-5355761.html
Thus, availing itself of the FFR phenomenon, and using the technique of “beat” frequencies, the Gateway system uses Hemi—Sync and other audio techniques employing the FFR phenomenon to introduce a variety of frequencies which are played at a virtually subliminal, marginally audible level.
https://www.independent.co.uk/arts-entertainment/music/features/the-music-industry-s-100-most-influential-people-5355761.html