It was developed in 1982 during the production of Return of the Jedi in an effort to theatre audiences would hearing what was recorded in the film studio, something that was not happening in most Theaters of that time as many of the subtle sounds were missing. Their 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 the filmmaker recorded it.

The THX Sound System is the only program of its kind to consider all aspects of a theatre's audio and visual performance, including architecture, acoustics and equipment. "THX is really a performance criteria; it's not a specific set of components," says Tomlinson Holman., Lucasfilm's Corporate Technical Director. This comprehensive set of standards includes rigorous specifications designed to optimize equipment, room acoustics, background noise levels, and projection and viewing angles. 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.

Now clearly this is not what most home theater users are going to be doing and there is a completely different program for that purpose which involves three Home THX product groups. These are:

Home THX Controller - includes multi-channel circuitry and the necessary electronic enhancements (Re-equalization™, Timbre Matching™, and Decorrelation™, and more) to successfully render the film sound experience in a home.

Home THX Amplifiers - built and tested to exacting specifications for distortion, noise, stability, and dynamic power required in a multi-channel sound system.

Other categories of Home THX Product include the THX Room Equalizer, Acoustically Transparent Projection Screen, Laser Disc Player and Interconnect Cable, but these three are the key cornerstones of a home system. Before any Home Theatre component can be THX Certified it must first pass a rigorous series of quality and performance tests and;

Home THX Loudspeakers - Left, Center, Right, Left Surround, Right Surround, and Subwoofer loudspeakers reproduce the clarity, localization, spaciousness, and timbre found in complex multi-channel soundfields. The Front speakers contribute proper tonal balance, intelligibility, and imaging, while the Surround speakers provide good envelopment and a sense of spaciousness.

All of the home components are further broken down into two categories. THX Select and THX Ultra but I won’t get into that here. In terms of home THX Speakers it can be summed up by saying that they are designed to deliver impressive and accurate 5.1 dialogue, music and surround sound without the need to constantly rearrange your living room by offering:

• Wide Horizontal Dispersion in THX Front Speakers gives you the optimum sound localization wherever you're sitting
• Focused Vertical Dispersion in THX Front Speakers increases dialogue clarity and imaging
• Dipole Technology in THX Surround Speakers gives you a sense of "envelopment" with the on-screen action
• THX Subwoofers are designed to deliver the most powerful bass performance from your Home Theatre System.

By now you might be starting to wonder how all of this gets packed into the ProMedia^TM V.2-400 speakers. Well the answer is it does not, at least not quite in that way.

Multimedia Speaker THX Specification
Lucasfilm THX® has actually developed a new THX specification for multimedia speaker systems with the five-piece (4.1) Klipsch speaker system the first to be certified. The speaker specification represents just a first step in the Lucasfilm THX’s expansion into multimedia, with additional specifications planned for other elements in the PC sound chain. "We plan to use patented technologies and our expertise in sound reproduction to certify a range of multimedia products, for the first time providing multimedia consumers with the assurance that they're getting the best performance possible," said Monica L. Dashwood, Lucasfilm THX General Manager. "With THX certified multimedia speakers, consumers will be able to enjoy feature films, computer games and music on their PC with the same top quality sound offered in movie and home theatre systems."

The THX multimedia speaker specification covers:

So with all this in mind we had some pretty high expectations for the Klipsch ProMedia^TM V.2-400 speakers when they finally arrived!

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