Monster sound system installed at the new home of 
the "Monsters of the Midway"

CHICAGO, IL USA - February 2004 -- Soldier Field, the home of Chicago's storied NFL football team the Chicago Bears, recently reopened after undergoing a massive renovation. The venerable old stadium, originally opened in 1924, had been the home field of the oldest team in the league for over 30 years. Though incremental refurbishments over the years extended the life of the facility, the team needed a new stadium on a par with other new facilities being built for NFL teams. After considering several options for location, the city of Chicago determined it wanted to keep the team in the heart of the city and launched a project to renovate the existing facility as part of a larger Lakefront Improvement Plan for the immediate area. The high-tech outdoor stadium design retains much of the old architectural charm that distinguished it through the years, yet incorporates modern stadium design elements intended to position it as a world-class sporting venue. Key among those elements is the high-performance audio system. The system had to meet the performance goals set forth early in the planning stages for the stadium while accommodating the architect's aesthetic concerns. This meant, in part, creating many custom loudspeaker enclosures. It was immediately apparent to the capacity crowd during pre-game opening festivities that the total experience of attending a Bears home game from now on will include rocking, high-energy sound. 

The design and consulting firm Wrightson, Johnson, Haddon & Williams, Inc.(WJHW) of Dallas provided system design, with Kevin Day of WJHW providing sound system design and Jack Wrightson handling project management duties. System installation was completed by SPL Integrated Solutions (SPL), with Don Alberg serving as Project Engineer based in Baltimore, and LD Parker as Site Engineer / Superintendent, Skip Warrington as Project Manager, and Jim Mascenic as Site Manager, based out of SPL Chicago. 

One of the equipment rooms with Crown CTs amplifiers. 
Soundweb units by BSS Audio also shown.

The game announcer uses a Crown CM-311AHS headset microphone, with Crown's patented Differoid noise-canceling response. This version of the CM-311A is designed to be mounted on headphones for broadcaster use. The mic signal is fed to a Soundcraft K2 console, then to a dbx 160A compressor. SoundwebT products by BSS Audio are used for signal distribution and processing. The hybrid point-source / distributed loudspeaker design for the facility implements three huge clusters, positioned along the top of the west end of the seating bowl, firing across the field to the other side. To provide a sense of scale, a set of 4 JBL Vertec 4889s are used as the near fill system. JBL Control Contractor series loudspeakers are used for distributed sound in ancillary zones and JBL custom speakers were designed for under-balcony. 178 CTs Series two-channel amplifiers fitted with IQ-PIP-USP3 modules power the entire stadium, ranging from the suites to the main clusters. The IQ-PIP-USP3 modules add an enormous amount of signal processing, control, and metering to the CTs amplifiers in addition to advanced error reporting and load monitoring capabilities. 

Two of three main loudspeaker clusters atop the stadium

The amplifiers were installed into seven different rack rooms with two dedicated to the clusters. A Fast Ethernet network was installed with Fiber optic cable for transporting the IQ Network communications between rack rooms and central control. Once the hardware was installed in the racks and the cable-plant was in place, making system connections was as simple as clicking a single RJ-45 connector into each component. This allowed the installation to be completed in a short time, and with very little difficulty. 

The Soldier Field IQ Network actively monitors the operation of the system, and detects potential problems before they have the opportunity to evolve into real ones. For instance, if a particular amplifier channel or loudspeaker driver starts to operate outside of a specified tolerance range, the computer will immediately display an error message alerting the tech staff of the anomaly. In providing an "early warning," potential problems can very likely be resolved prior to triggering customer complaints or, worse yet, catastrophic and costly damage to audio equipment. Bradford Benn, US Business Development Manager for Installed Sound at Crown commented about the IQ Network, "The fact that our IQ Network works on common Ethernet networking technology was a real benefit for this project. When it was time for SPL to do the installation, they didn't have to worry about a lot of special considerations to make the network function. Common networking design and practice is all that is required to get up and running."

Crown International, a Harman International company, manufactures amplifiers, microphones, and systems control products for professional audio markets worldwide, with corporate headquarters located in Elkhart, Indiana. For more information, please visit Crown online at


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