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THX is a certification system for theaters. It is like quality control for the movie-going experience. It is a system developed by the sound people at LucasFilm, a company founded by the man behind the Star Wars movies, George Lucas.

Background Information

Depending on who you ask, "THX" stands for a couple of things. Some say that it comes from George Lucas' first film, THX 1138; while others say that it stands for the "Tomlinson Holman eXperiment".

Tomlinson Holman is a sound engineer that worked for LucasFilm back around the time that Return of the Jedi was being filmed. George Lucas was putting a lot of effort into making the Star Wars films sound as good as they possibly could, but was continually disappointed in how they sounded once they got to your local theater. So Mr. Holman came up with this certification process for theaters that will guarantee the best possible reproduction of what was heard in the mixing room when the film sound was recorded.

What THX Certification Means

The THX certification process starts with the actual theater design. Sound from external sources such as heating and air conditioning, the adjacent theaters and even from the road out front must be at an absolute minimum. Otherwise the movie goer would be distracted from the on screen performance.

Other items that the THX certification process looks at are the angle at which the image is projected onto the screen. How bright the image looks from certain seats in the theater and how all of the speakers are aimed and calibrated. In fact, the THX certification process even specifies the type of speakers and amplifiers that must be used!

After the theater is built and all of the equipment installed, THX Technicians must come out and make sure that all of these specifications have been met. They use sensitive microphones and other assorted equipment to take all of the measurements. If a theater passes all of this, it becomes "THX Certified". But that is not quite everything. Every year, technicians return to re-check the theater and make sure that everything is still properly aligned, calibrated, and soundproofed.

All of this ensures that you, the movie goer, will receive the best possible movie-going experience when you are seeing a film presented at a THX Certified theater. Is it possible to have a bad experience at a THX theater? Sure, but it's much less likely than with non-certified theaters.

When you visit a THX-certified theater, you can provide THX with feedback by using their Cinema Survey Form.

If a theater has Dolby Digital or DTS, do they still need THX?

Simply put, yes. THX is not a sound system, it is a process that certifies many things, including the installed sound system, from the amplifiers to the speakers, to how the theater is constructed.

For the best performance, you want digital sound in a THX-certified auditorium.

Have you ever gone to see a drama, only to have the explosions of the action movie next door disturb the best moments of the movie? This is called sound leakage, and it's just one of the annoyances that you won't experience in a THX-certified auditorium.

Have you ever heard the projector running during quiet periods of a movie? That's another annoyance you won't have when going to a movie in a THX-certified auditorium. Special care is taken to make sure that outside noises don't disturb your enjoyment of the movie.

Many complaints about the sound being too loud in a theater isn't because the volume knob is turned up too high. The real problem is that the sound system and the auditorium haven't been tuned for the best sound quality. The most common reason for complaints is caused by the sound being too harsh, especially in the higher frequencies. This can be a result of bad quality speakers, speakers with broken components, or an issue with the room emphasizing some sounds while making other sounds too soft. You can relate to this if you've ever taken a cheap radio and turned the volume up too high. The speakers just can't handle the high volume, so while talk radio might sound just fine, very dynamic music might be painful to listen to.

The BigScreen Cinema Guide supports the THX certification of theaters, since it's one of the few ways that moviegoers have of knowing where to find good presentations. While non-THX theaters can also provide good presentations, it's very difficult for the average person to know one way or another just by looking at showtimes for a list of theaters.

Look for the THX logo to the right when viewing our showtimes to find the movies and theaters featuring THX-certified performance.

For more information

For more information about these THX specifications and other information about THX, please take a look at the official THX web site.