In a project that completed in February 2020, Audio Logic Systems of Eden Prairie, MN deployed d&b audiotechnik V and Y-Series loudspeaker systems in an audio upgrade for the Carlson Family Stage within Northrop at the University of Minnesota.
“As the modern use of the Carlson Family Stage has grown the Northrop staff expressed the need for a system upgrade in the venue to meet touring riders of the A list national and international performances targeted by the venues artistic planners,” states John Simshauser of Audio Logic Systems.
The Carlson Family Stage within the historic Northrop at the University of Minnesota is the venue’s main theater, seating up to 2,700, with main floor seating of 1,100 and additional three wraparound balconies. Northrop consists of multiple performance and rehearsal spaces, a gallery, café and coffee shop, and offices for four university departments, and has adapted this year in light of the pandemic by offering online performances and limited-capacity live events that follow safety guidelines.
Simshauser notes that the auditorium has excellent natural acoustics and serves as a good place for amplified performances as well, albeit with some challenges due to the physical variations of the room seating. “The room is very intimate, minimizing the viewing distance for all seats by utilizing varied rake seating and varied balcony depths,” he explains. “Specifically, the upper balcony (The Gallery Circle) has a 34-foot longer acoustic throw then the lower balconies. Due to this room configuration, covering the room with a traditional line array deployment presented unique opportunities to implement advanced features of d&b loudspeaker systems like ArrayProcessing, which optimizes a line array’s tonal and level consistency over the entire coverage area.
“The three biggest challenges for sonic linearity throughout the seating area were the varying depths of the balconies, the limited trim height of the PA (impacting specifically the middle and upper balcony seating), and the extreme splay angles of the Y-Series center system required to cover the full height of the room.”
The sonic character of the large upper balcony significantly differs from the floor and lower balconies, specifically in the upper mid- and high frequency ranges. “For the V system, ArrayProcessing naturally addressed the challenges of the third balcony by taking into account the unique dimensions of that seating area,” Simshauser days. d&b ArrayProcessing settings for the V arrays shifted the level over distance plus 3 dB from the non ArrayProcessing performance (or “intrinsic”) while using a Glory 5 processing emphasis.
In relation to the upper balcony, the array (V-Series system) trim height is very low, less than half the height of the top row of seating (39 feet versus 89 feet). For the main V system to cover from the orchestra pit to the upper row the splay angles are greater than in many systems. ArrayProcessing addressed the low trim height challenge by calculating array frequency response over the entire range of seating distances.
For the Y-Series array, the system specification called for a minimal number of boxes in the array due to sight line restrictions. There are eight Y12s in the system. Four of the eight boxes are at a splay of 13 degrees, and six of the eight boxes have a splay of 9 degrees or greater. Simshauser: “Without ArrayProcessing the level variance at 4K between array elements from floor to balcony was plus/minus 18 dB. ArrayProcessing effectively minimized the gaps in HF due to the extreme splay and the uniformity of HF coverage was greatly enhanced. To cover seating with such a large rake and throw distance variance, ideally twice as many Y12s would have been deployed in this situation. ArrayProcessing should never be a substitute for physical box count. However, in situations like this where box count is limited by external factors, ArrayProcessing is an extremely valuable tool to maximize performance and smooth array element interaction.”
The loudspeaker arrays are configured as a left and right V array for music performance with a center Y array focused on speech. All arrays can be used as one system. Balancing the tonality of the system, both the V system for music and the Y system for speech reinforcement is especially challenging in the upper balcony. ArrayProcessing looks at the entire system and maximizes interactions and manages the overall tonal character of all elements.
The system also has significant subwoofer support in the form of eight flown V- SUBs and four SL-GSUBs. Simshauser notes that, “Due to the exceptional room acoustics, the distributed low-end reinforcement, and an all cardioid sub design, the low end is tight and impactful from the floor to the upper balcony. The final goal of any audio system upgrade is to make a significant positive impact in the daily experience of the audience, the performers, and the technicians.”