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Electronic architecture systems work by substituting virtual reflecting surfaces (that is, loudspeakers) where architecturally reflecting surfaces are lacking in order to compensate for excess sound absorption in a room. At the Center, this meant installing approximately 75 loudspeakers into the body of the ceiling and under the balcony. Two microphones hanging forward of the proscenium pick up sound that is specially processed to simulate a mix of early reflection energy and acoustic decay with the frequency content adjusted to "fill in" the missing components of the room's natural sound. This energy is then delayed to the LARES systems and distributed among the embedded speakers.

"Listeners don't identify the speakers as the sound source," says Scott Leonard, president of Professional Audio Designs, the Wisconsin-based company who installed the audio systems in the hall. "The audience simply responds to the music in the room."

Rodney Stickrod, BCPA Technical Director, and Russell Cooper, JaffeHolden acoustical designer. The substructure of the 81' wide x 40' deep stage was retained in the restoration, but the stage deck was replaced with tongue and groove maple. The floor now meets all current dance requirements.

"This is a hall with good 'bones,'" says Cooper. "It works well for reinforced music, but it needed help to be a really good venue for acoustic programs. Bloomington is a community that doesn't have the resources or even the need for a multi-million dollar concert hall that will be used for one purpose. Electronic architecture is the key for communities like Bloomington to get a really fine facility that serves their needs perfectly without having to change the existing hall's, volume, dimensions, and finishes. The investment in the system is more than paid for by the amount of money they would have spent on raising the roof and adding adjustable acoustics, which for this building was an impossibility for zoning, historic, as well as financial reasons."

The LARES-based electronic architecture system was designed and programmed by JaffeHolden's Systems Group with Steve Barbar, principal of Lexicon Acoustic Reinforcement and Enhancement Systems. It has three basic pre-sets: for symphonic music, chamber, and small group ensemble. For acoustic music programs, the electronic architecture system is turned on and a program-appropriate preset is selected.

"I have to admit, I was a little skeptical when I heard that an electronic architecture system was being installed," says BCPA Theater Technical Director, Rodney Stickrod. His experience with electronic architecture in another city and another hall was not successful. A poorly designed enhancement system unlike a less-than optimally designed sound reinforcement system, can leave a bad taste for the technology in general. Further, Stickrod was skeptical that an electronic architecture system could make enough of a difference in the acoustic response of the hall to be discerned by the average listener.

"I moved all around the hall during a rehearsal with the Wesleyan Civic Orchestra," Stickrod says, "listening with the JaffeHolden system on and then with the system off, repeatedly. Not only can you tell the difference when the system is on or off, but what you hear is a beautiful difference. I was very impressed." Impressive also, he says, is how easily the system is maintained; it acts as a part of the architecture, with no need for tweaking or any user intervention.

New Mechanical, Electrical, Plumbing
A ballroom that can seat 1000 is directly below the concert hall. The hall was basically gutted, including the seating, but the concrete floor of the hall remained basically untouched. "It's an interesting floor," says Executive Director Marquis. "It's pre-cast with integral rebar, no steel beams supporting it, unusual for the period." The space between the hall floor and the ballroom ceiling was an open-air plenum, he says, but now houses duct work, new plumbing, and electrical conduit. "Other than doing some repair and relocating floor ducts for the HVAC system, it remains as it was in 1921. The AC is still in the floor or the ceiling of the ballroom, but we replaced the cooling unit outside, at JaffeHolden's suggestion, and sealed up windows on that side of the hall to shut out noise." Because of the structural arrangement between the floor of the hall and the ballroom ceiling, simultaneous use of the hall and the ballroom beneath was effectively ruled out.

Sound Reinforcement System
For pops and other amplified music, JaffeHolden also designed a front of house system. Technical Director Stickrod designed the monitor system.

"Early in the design process, the intent was to provide a relatively small reinforcement system," says Turpin, "because the planned program mix did not include shows that needed high-level reinforcement. However, as construction proceeded and the City of Bloomington started to look at programming in more detail, this program mix started to change."

With Stickrod's strong advocacy, BCPA owners decided they needed to beef up the audio FOH system to handle a broader range of shows. Once that decision was made, and the FOH system (consisting entirely of EAW loudspeakers) was installed, work turned to getting maximum performance out of the rig. "Mark (Turpin) worked very hard to get the system where I wanted it to be," says Stickrod. "For some shows, like The Urban Funk Spectacular [Sept. 29 th], I knew I needed the system to be loud. It could already handle pop and other formats, but I needed the system to handle a full range of acts."

"In the end, Mark tuned the system from the bottom up. Instead of starting from the top speaker in the center cluster and working his way down, because we have such a deep balcony fill, he tuned the system from the bottom up, from the bass to the center cluster. This was the opposite of the way he would normally tune a system, but when he did, that's when we hit the mark I was looking for."

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