The THX Sound System was developed in 1982 during the production of Return of the Jedi. Inspired by George Lucas’ interest in upgrading film presentation standards in the industry, Lucasfilm’s Corporate Technical Director, Tomlinson Holman, began to identify problems related to theatre sound. Holman noted theatre audiences were not hearing what was recorded in the film studio – that many of the subtle sounds were missing.
His innovative approach was to consolidate existing performance standards into a new system which included theatre acoustics as well as sound equipment. THX (named after Lucas’ first feature film, THX 1138) is a sound system designed specifically to reproduce film sound exactly as it was recorded by the filmmaker.The THX Sound System is the only program of its kind to consider all aspects of a theatre’s audio&visual performance, including architecture, acoustics and equipment.
‘THX is really a performance criteria; it’s not a specific set of components,’ says Holman. The system was created to complement advances made by Dolby®Laboratories in decoding sounds in the sound track which concentrates on the ‘A-Chain’. The THX Sound System concentrates on the ‘B-Chain’ of a theatre’s sound system. The ‘B-Chain’ is comprised of customized acoustical design work for each auditorium, a special screen speaker installation method, a proprietary electronic crossover network, and rigorous audio equipment specifications and performance standards. Upon completion of a THX Sound System installation, the theatre is tested by a THX engineer to make sure it meets both THX environmental technical criteria and recommended industry standards for high quality visual and sound presentation. Theatres are re-certified to ensure that optimum quality is maintained.
A certified THX theatre carries several important advantages for the movie-goer. The audience enjoys a more naturally balanced sound that uniformly reaches every seat in the auditorium, improved dialog intelligibility and decreased bass distortion. Better stereo localization makes the sound appear to travel across the screen with action. A frequency range that is wider by a full octave in both bass and treble allows patrons to hear higher highs and lower lows. The combined result is the reproduction of the same clear, dynamic sound originally created by the filmmaker.
The exhibitor’s unique challenge is to create an environment that keeps the magic of the big screen alive. With installations in more than 1400 certified THX theatres and dubbing facilities worldwide, the THX Sound System has become a premium standard for quality film presentations.
Digital recording technologies such as Digital Theatre Systems (DTS), Dolby Digital (SR D) and Sony Dynamic Digital Sound (SDDS) can provide a significant enhancement in theatre sound. But digital alone is not enough. Digital recording affects only the encoding of sound information onto a film; it does not involve the aspects of sound reproduction that are addressed by the THX Sound System, such as amplifiers, speakers and room acoustics. Digital recording and THX work together to produce the best sound experience possible.