The certification the THX
group apply's to equipment that has undergone and passed its rigorous testing. THX equipment
must comply to a certain level of quality that is determined by the THX group
to enhance the listening pleasure of MOVIES.
This certification testing must be paid for by the company that wishes their equipment to be certified. This increases the cost of said equipment.
THX certification originally was only set up for Movie Theaters. Slowly THX released Home Theater requirements and HT equipment began to be certified.
The basic requirements for a Movie Theater to be certified are based on increasing the enjoyment and quality of watching a movie. This deals with the sound, screen and seating of the theater. The sound must pass the THX test at certain seating positions. The screen must be designed in a certain way(basically how flat it is), and must have a specific reflection property based on the theater it is in. The seating must also allow for unobstructed view of the screen as well as be set up so that one can comfortably enjoy the movie.