"Swan Hall had an outdated audio and video system," said Jim Smith of HB Communications. "We were asked to do a complete overhaul. However, the shape of the room and the layout of the seating caused us to make some inordinate speaker and placement choices. The JBL CBT100LA column speakers and Control 67 HC/T pendant speakers proved to be the perfect solutions."
Swan Hall is a wide, flat room that has about 200 seats in 11 tiered rows, with a sloped floor, making the seating higher in the back of the hall than in the front. However, the ceiling remains at the same height-which means that the people sitting in the back of the room have their heads closer to the ceiling than the people in the front.
"The loft ceiling was also a potential acoustical nightmare," Smith noted. "It was completely bare with exposed trusses and duct work and no type of acoustic treatment-even a typical dropped ceiling would have reduced the amount of echo and reflections considerably."
Smith deployed two JBL CBT100LA column speakers-one on each side of the projection screen located at the stage area at the front of Swan Hall. "The narrow column design and the tight pattern control of the CBT100LA allowed us to direct the acoustic energy straight back to the seating, as opposed to a typical speaker that would have a much wider dispersion pattern and would not work nearly as well," Smith said. "The CBT100LA has a narrow vertical and wide horizontal coverage pattern that allowed us to direct the sound into the seating area without going into the ceiling loft above, which would have caused a lot of problematic reflections."
To tackle the challenges of the sloping floor and the difference in ceiling height between the front and the back of the room, HB Communications chose to augment the system with the JBL Control 67 HC/T pendant speakers. "We realized the Control 67 HC/T pendant speakers were the ideal solution because they have a narrow down-firing dispersion pattern and can be hung from a ceiling, so we were able to place them in three rows of four speakers each, suspended above the seats," Smith noted. "This allowed us to precisely control the sound coverage and direct the sound exactly to where we wanted into the seating area, without putting any sound into that echo-prone ceiling loft. This configuration also enabled us to achieve a good balance between the stage area and front seats, and the rest of the hall."
Swan Hall is used as a classroom and lecture hall and also for film studies, so the University wanted a sound system that could be used for both applications and was within a reasonable budget. To reproduce the full-range audio required of movie soundtracks, HB Communications augmented the main speakers with a pair of JBL ASB6115 front-firing 15-inch subwoofers, mounted from the ceiling to the left and right of the projection screen and the CBT100LA speakers. The CBT100LA speakers and ASB6115 subwoofers are driven by Crown Audio XLS2500 amplifiers, while the Control 67 HC/T speakers are powered by Crown CTs4200 amps.
"We used the Crown amps because they have onboard digital signal processing that lets us optimize the performance of the loudspeakers and subwoofers," Smith pointed out. "Because the ceiling is flat and the seating is tiered, the pendant speakers at the back of the hall are closer to the listeners' ears than the speakers at the front of the hall. The DSP in the Crown amps enabled us to make adjustments for each row so the sound stays consistent for everyone."
"The University of Rhode Island is very happy with the results," concluded Smith. "In fact, when we finished the installation we demoed it by playing a live version of the Eagles' 'Hotel California'-and it wowed everyone."
As the largest university in the smallest state, the University of Rhode Island is known regionally and worldwide for its innovative, big ideas, adaptive intelligence and breakthrough solutions to today's puzzling problems. URI's pioneering research extends the University's influence well beyond its coastal borders, while its unique interdisciplinary courses provide its 16,000 undergraduate and graduate students with global opportunities in an intimate environment.
HARMAN (www.harman.com) designs, manufactures and markets a wide range of audio and infotainment solutions for the automotive, consumer and professional markets - supported by 15 leading brands, including AKG(r), Harman Kardon(r), Infinity(r), JBL(r), Lexicon(r) and Mark Levinson(r). The Company is admired by audiophiles across multiple generations and supports leading professional entertainers and the venues where they perform. More than 25 million automobiles on the road today are equipped with HARMAN audio and infotainment systems. HARMAN has a workforce of about 13,000 people across the Americas, Europe and Asia, and reported net sales of $4.3 billion for the twelve months ended March 31, 2012.
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