Holophonics is a binaural recording system created by Hugo Zuccarelli, that is based on the claim that the human auditory system acts as an interferometer. It relies on phase variance, just like stereophonic sound. The sound characteristics of holophonics are most clearly heard through headphones; though they can be effectively demonstrated with two-channel stereo speakers, provided that they are phase-coherent. The word "holophonics" is related to "acoustic hologram".