“The Ravinia team is thrilled with the beauty of this acoustic shell,” stated Jeffrey P. Haydon, Ravinia Festival’s President & CEO. “We’ve received so many compliments from guests and musicians, and to see it evolve from the early renderings into the real thing has been incredible.”

Wenger contributed to the renovation of Ravinia’s Hunter Pavilion in Highland Park, IL, by designing, manufacturing and installing the largest and heaviest acoustical shell in the company’s history. The custom outdoor shell supports Ravinia’s dual role as the summer home of the Chicago Symphony Orchestra and a major venue for touring shows and rock/pop concerts.

Massive Moving Walls. The shell is massive by any measure. Each of the two motorized, pivoting walls weighs 7.5 tons, roughly equal to three Ford F-150 pickup trucks, and is 29 feet tall by 32 feet wide. Two narrower, non-motorized pivoting walls each weigh 1.75 tons and span 8 feet. Additional fixed walls bring the total acoustic surface to 5,500 sq. ft., greater than eight standard highway billboards.

The giant pivoting walls open and close like a book. The larger pair moves by motorized trolley, while the narrower pair is moved manually. For orchestral performances, the walls pivot inward to shape the stage environment. For amplified events, they pivot outward and are masked by black curtains.

Architecture, Acoustics and Outdoor Durability. The shell’s distinctive appearance was designed by Michael C. Barnes, AIA, LEED AP, Principal Architect with Lohan Architecture, who was inspired by the art glass windows of Ravinia’s historic Martin Theatre. LED illumination and metallic accents emphasize the varied geometry of the chevron-patterned walls, which demanded highly complex fabrication.

Because the Pavilion is an open-air venue, the shell also must withstand extreme weather variations. The walls were built from steel tubing, urethane foam, exterior-grade plywood and a vinyl architectural finish.

Threshold Acoustics engineered the shell’s acoustic performance to improve musical presence for performers and facilitate onstage communication. The shell combines significant mass with reflective lower sections, diffusive upper surfaces and ceiling panels that balance sound and control loudness.

“Wenger really has the capability of a specialty shop,” said Todd Hensley, Director at Schuler Shook Theatre Planners. “They balanced the need for a durable, deployable shell with the acoustician’s need for mass and the architect’s vision for beauty.”

Lighting, Rigging and Controls. The shell’s winged ceiling panels fold and store compactly to maximize limited rigging space. Wenger Lieto™ lights in the panels’ fixed center sections are stage-facing and usable for all programming.

Rigging solutions include PowerLift^® and Titan^® hoists in a new configuration that redirects lift lines overhead to improve catwalk operations. Wenger’s Vantis^® controller manages the ceiling panels and other motorized rigging.