What Is A 4-D Theater?

Regional theme parks face the same challenges as the major national parks: It takes new attractions to keep up attendance. Of course, regional parks don't have Disney-sized budgets, which can make the process of attraction design particularly challenging.

So how can a smaller amusement park offer an experience that will attract new visitors? 3-D films used to be a sure-fire method, but with the debut of Disney's Honey I Shrunk the Audience back in the early '90s, the major theme parks took 3-D to a higher level, equipping the theater with effects such as water spritzers, lighting effects, and even "leg ticklers." These shows, dubbed "4-D," were a big hit and Honey was soon joined by several others, including more and more of the smaller parks, since the equipment can be used for show after show, without requiring a major refit.

Bellewaerde Park, in the southwest of Belgium, decided to extend its operating calendar and needed an indoor hook that could be easily reconfigured for the different seasons. They settled upon a 4-D theater.

"As we are a combination of family theme park and animal park with large amounts of landscaping, we wanted a film that met the same spirit," explained Filip Dewitte, Bellewaerde's general manager. "Showscan's Forest Adventure is both family-oriented and full of action. It tells the story of forest animals endangered by a man-made fire. This film was ideal for us."

Kraftwerk provided the seats and special effects. Barco I-con H600 projectors were selected to deliver the 3-D video.

Bellewaerde turned to Alcorn McBride for the high-definition playback and control equipment. Since Alcorn equipment has been in use in almost every major theme park in the world, it holds an extremely high reliability factor. The company also probably has more experience in 4-D theaters than any other audio/video manufacturer.

Henry Corrado, director of Alcorn McBride's French subsidiary, explained, "4-D theaters need fairly complex systems with perfect reliability, while often being run by non-specialists. So all of the equipment must sync and run perfectly, every time."

At Bellewaerde, the heart of the system is an Alcorn McBride V16+ show controller connected to an IO64 input/output module. The use of a scriptable show controller means it's possible for non-technical users to change the theater timing if the show changes. Alcorn's Digital Binloop is used as a 6-channel discrete audio reproducer, a master time-code source, and as a backup for the main video sources. The Digital Binloop is a modular, Compact Flash-based audio/video player, and is used in the majority of the world's theme park attractions.

The main video sources for the show are two Alcorn McBride Digital Video Machine HD (DVM/HD) high-definition video players. The DVM/HD is one of the few pieces of HD gear designed to run in perfect frame sync, a necessity for the 3D effect to work.

"The selection of a single manufacturer for all of the audio, video, control, and sourcing equipment made the installation much easier," said Steve Alcorn, president of Alcorn McBride. "When the programmer from our French subsidiary showed up at the site, he was already familiar with all of the components, so connecting everything and getting it all to sync properly was a snap. This allowed him to focus on the aesthetics of the show."

Because Compact Flash sizes aren't yet big enough to hold a full-length high definition show, the DVM/HD stores its video on hard drives. While hard drives are more reliable and less expensive than film, they do occasionally fail. To prevent interruption due to HDD failure, a pair of video reproducers, installed in the Digital Binloop, detects the failure and automatically switches the video feeds to standard video and alerts maintenance.

Extron sync generator is used to feed all video players, Digital Binloop and Show Control systems with a video sync signal. This guarantees left and right eye sync of the 3-D video and tight coupling of audio to video.

A Peavey X-Frame and 8 x 8 expansion box is used for sound reinforcement. The loudspeaker configuration is close to a conventional theater. JBL 4675 and 4645 subs are used for behind-screen reinforcement. Because water effects are used in the theater, waterproof control 30 cabinets provide the surround sound. The entire PA system is powered by Crown, and each surround speaker has a dedicated amplifier channel to allow careful level adjustment.

An Alcorn McBride LightCue controls the theater lighting. The Light Cue is a DMX recorder. It allows a lighting designer to create the show using any lighting board and then recording all of the cues onto the Light Cue. The lighting board can then be removed. The LightCue locks to the time code provided by the Digital Binloop.

The project was completed in just a few months. Stefan Lemey, Bellewaerde's technical manager, explained, "As we worked only with the best suppliers and manufacturers, we had no problems that couldn't be solved quickly and easily, and most importantly, within budget."

The theater can also be configured for corporate events, with the presenter having the ability to trigger any of the built-in effects. This is excellent for creating dramatic effects and even for waking people up, when needed.
The project is clearly a success, Dewitte added, "More than half of all our guests visit the attraction, and we expect this percentage to rise considerably. Guest satisfaction continues to be outstanding."