Built in the early 12th century, the stately Romanesque Cathedral of Sessa Aurunca in Italy, recently installed a Meyer Sound CAL™ column array loudspeaker system to solve a speech intelligibility problem commonly found in highly reverberant spaces.
The cathedral's high, vaulted interior is acoustically reflective, with stone walls and columns surrounding a tile mosaic floor, and hard plastic seating. To bring speech clarity to this reverberant space, two CAL 32 loudspeakers were deployed to focus acoustic energy precisely on the congregation seating area with minimal energy exciting the adjacent hard surfaces. The CAL loudspeakers are adjustable to one degree of vertical dispersion.
“The cathedral is an ancient and historic building, and almost nothing is permitted that would alter the appearance of the interior,” says Lorenzo Benigna of system provider Linear Sound S.r.l. “Our objective was to design a new system that would be effective, yet practically unnoticeable.”
The two slender CAL 32 loudspeakers are mounted flush against the cathedral’s sidewall to remain unobtrusive, with each vertical beam tilted down 10 degrees. Their vertical dispersion angle is set at 30 degrees to project a uniform wedge of highly intelligible sound precisely upon the seating area.
“There really is no comparison to the cathedral’s old system,” points out Benigna. “CAL is an exceptional system with superior performance not just for speech, but for music as well.”
The system also employs eight MM-4XP and four MM-4XPD self-powered loudspeakers to discreetly fill seating area spots that are acoustically shadowed. The units receive audio signal and DC power over a single cable from dual MPS-488HP power supplies (48 V DC).
“The exceptional directivity of the MM-4XPD was very helpful, as these speakers were placed near the microphones,” says Benigna. “They provide excellent coverage without producing feedback.”
The system design was a collaborative effort involving Benigna and Giovanni Bugari of Linear Sound, together with Adriano Conte, a church AV consultant.
The Cathedral of Sessa Aurunca is a medieval basilica with a vaulted portico and two aisles formed by 18 columns. It was constructed in 1113 using materials from the ancient Roman temples of Mercury and Hercules. With a population of about 23,000, the city of Sessa Aurunca is located 140 kilometers southeast of Rome in the region of Campania.