The National Constitution Center, which opened, appropriately enough, in Philadelphia on July 4th, is designed to emphasize the importance of the American Constitution, both by presenting how it was developed in the first place, and by demonstrating its relevance to US Citizens and the World today. The exhibit area of the Center, in The Richard And Helen Devos Exhibit Hall, has one of the highest concentrations of Audio-Visual and Interactive presentation to be found anywhere, and has proven to be a hit with the public.
"Freedom Rising" in the Kimmel Theatre at the National Constitution Center.
Pei Cobb Freed were the architects of the National Constitution Center Building. Ralph Appelbaum Associates designed the exhibit area; Electrosonic Systems Inc was the AV systems integrator. Maltbie and Associates served as the main exhibit contractor, and appointed Maris Ensing to act as their project manager in charge of AV software and hardware integration. Jaffe Holden Acoustics provided acoustic advice for both the show and the exhibit area.
The introductory show, “Freedom Rising”, is presented in the 350-seat Kimmel Theatre. This is a circular space with a central floor space and steep raked seating. The show lasts 17 minutes, and is given every 25-30 minutes depending on visitor traffic. Narration is normally by a live actor (a team of eight actors is required) although there is an alternative version of the show that uses recorded narration.
The main visual content is presented as a 360° image that surmounts the top row of seating; this requires the use of 10 Sanyo PLC-XF30NL projectors, each producing an image nearly 25ft (7.5m) wide. The size of the images requires the use of projectors with high light output (5000 lumens). The projectors are fed from a multi-channel video server providing 10 synchronized channels of Y/C analog video. This gives excellent video quality at the viewing distances that apply in the theatre. The surround screens are supported by an 18ft (5.4m) diameter circular image projected on the floor. This is derived from another Sanyo 5000 lumen projector, this time sourced from a High Definition player because of the nature of the images and the shorter viewing distance. The high-definition video imagery is augmented by stage lighting and gobo projection. Toward the end of the show, five scrims drop down from the overhead structure that supports the main projection and lighting equipment to envelop the actor. The 18ft × 9ft (5.4m × 2.7m) screens all show the same portrait format image, which is derived from a second High Definition player. The High Definition Video Players are manufactured by MediaSonic (a Division of Electrosonic).
Audio is derived from a 360 Systems TCR-8 eight-channel hard disc player, the outputs of which are processed by Mackie DX810 DSP equalization and routing equipment before being fed to the power amplifiers and multiple loudspeakers. The loudspeakers are installed in two main groups of 10; one group behind the ten surround screens, and the other arranged as five pairs mounted within the central lighting grid. They are supported by two sub-bass loudspeakers. The actors use Countryman Isomax E6 wireless microphones, the aim being to ensure that the audio quality is the same whether a “live” or pre-recorded show is being given, and regardless of which actor is performing. In practice this means that each actor has his or her own individual microphone, and that the DSP system provides multiple equalization and volume level “presets” that are selected according to which actor is performing. Other equipment includes Tannoy i5 and i12 speakers, Bag End sub basses, and Crown amps.
Show control and system monitoring is by Electrosonic ESCAN™. This controls all video source, audio source, audio equalization, auxiliary effects and show scheduling directly, and provides SMPTE timecode and initializing commands to the lighting control and rigging control sub-systems.
At the conclusion of “Freedom Rising” visitors leave the Kimmel Theatre at its top level and enter an annular exhibition hall that surrounds the theatre, which has as its theme “The American Experience.”
The American Experience Exhibit.
Surrounding this area at high level is a series of glass panels that carry the words of the Constitution; directly below this a series of exhibits explore how the Constitution has shaped US History over time. Artifacts, walk-in environments, video overviews, interactive computer displays and conventional graphic panels are all used as means of presentation.
A central path through the exhibit area is organized according to the words of the preamble--“We the People”...“of the United States," etc--which provide the themes of exhibits that explore aspects of citizenship and government. Most areas are surmounted by large screen video projection, while at floor level there are interactive and hands-on activities. One particularly popular exhibit is a blue-screen experience where visitors can enact being sworn in as President. Later, as they leave the Center, they can collect the photo.
The “American Experience” requires intensive audio-visual and interactive support. There are approximately 60 computer interactive exhibits, 50 video replay screens, and 10 audio only exhibits, all operating within a comparatively compact area. Image display is by a mixture of LCD flat panel (both conventional and “touchscreen”), plasma display panels and projection. Gear includes Sanyo PLC-XP46 XGA LCD 4400 lumen projectors, NEC MT1060 XGA NTSC LCD 2600 lumen projectors, Sharp 20” LCD displays, Dataton Watchout production software, and Alcorn McBride 8Traxx digital audio players.
The American Experience Exhibit.
The overriding design requirement for the AV system was to ensure that only a minimum of equipment should be at the display point, and that all equipment should be easy to maintain. This in turn led Electrosonic to use their “conventional” system architecture whereby all source and control equipment is rack-mounted in central control rooms – in this case the building layout is such that a single main control room is sufficient. The images on the interactive exhibits are distributed in RGB form using CAT-5 cables.
All audio channels (of which there are nearly 120) are routed through DSP equipment and multi-channel power amplifiers. This arrangement not only allows the optimization of each channel according to the individual exhibit construction, it also permits master “audio scene” control to provide different sound levels according to visitor traffic and special events. The density of the audio elements in the space, the openness of the exhibit design and the reflectivity of the surface materials meant that great attention had to be paid to directing sound to the desired location. This was achieved by using custom directional speakers and by augmenting traditional main speakers, which are mounted behind video screens, with small floor-mounted speakers on delay channels. This spreads the sound through the space without apparently increasing the overall volume level. Electrosonic worked closely with Jaffe Holden Associates and Dakota Audio to achieve the final result. A notable point about the NCC installation is that there was an aesthetic requirement to hang nothing from the ceiling. As a result, the great majority of the exhibit audio is finally delivered through floor-mounted loudspeakers sited behind floor level grilles set into the concrete. This approach required very close co-operation between contractors at the building stage.
The entire exhibit AV system is under the control of Electrosonic ESCAN. This schedules the operation of the exhibits and monitors their performance. All video servers, interactive computers and interface devices are on a LAN (Local Area Network) through which ESCAN carries out its controlling and monitoring functions. These include daily power-up and power down routines, simple exhibit sequence control, checking that interactive computers are running correctly, checking projectors are running correctly, checking projector lamp running hours, controlling the audio DSP subsystem, and controlling various other sub-systems and devices.