Located in the South Korean province of Jeollanamdo, the 6,000-capacity Jeonnam Yeosu Arena at Jeonnam Sports Park in Yeosu City has recently undergone a substantial renovation, designed to upgrade this popular facility. High on the list of areas targeted for improvement were the venue’s sound and video systems, the audio component in particular being a fairly basic system whose limitations had become apparent over the years.

The Sports Park is used principally to stage local sports games while the arena hosts pro basketball during the season. It is owned and operated by the City of Yeosu, which decided last year that a completely new audio system was required to bring the arena into line with national and international standards for speech, music and voice evacuation, and put the design and installation contract out to tender among leading Korean audio suppliers.

The Jeonnam’s construction is typical for a large sports arena, with concrete and brick walls, a steel framed roof with multiple tubular steel braces and hard plastic seating. This familiar combination of materials and the arena space turned out, on detailed analysis, to create long reverberation times and a number of acoustically problematic areas within the facility. A system was required that would deal with these challenges and deliver an enjoyable and clear sound to the arena’s customers.

Among those invited to tender was DaiKyung Vascom of Seoul, one of Korea’s leading pro A/V and public address sales, distribution and manufacturing specialists, to whom the contract was eventually awarded.

The first stage of this process, explains Mr Dae Hyun Han, Sales Director of DaiKyung Vascom, involved a competitive demonstration between their recommendation, a Renkus-Heinz CT5 central cluster loudspeaker system, and several other major loudspeaker brands. The demonstration featured a typical selection of the arena’s range of playback, voice announcements and live music as the sound sources.

“The management wanted to know that the system that was chosen would be of world-class quality, very compact and lightweight in relation to its power output, and backed up by a specialist installer with the resources to support it fully in future years,” comments Mr Dae Hyun Han. “Those were the first aspects they wanted assurance about, and then they naturally wanted to hear it and evaluate its performance for themselves.”

A further system design challenge for those tendering was to propose an installation infrastructure that would allow the chosen loudspeaker system to be suspended with an evenly distributed roof loading.

Mr Dae Hyun Han of DaiKyung Vascom commented: “The client emphasised during the tender process that they wanted the best possible sound quality and coverage for the available budget, as they were determined to have a first class audio/visual system to benefit their fans.
“In Korea most public sports venues belong to the government,” he adds. “There is a small number of designers and installers who are qualified for this type of contract and the market is very competitive. Sometimes a loudspeaker model is chosen because of its international status – having won awards or through special promotions; it’s very important to be able to show that a product is a world-wide leader when the project is high profile. Sometimes a contract is won because of a successful demonstration, which was the case at Jeonnam Arena – the client said it was great sound and we were awarded the contract partly because of the audio quality and partly because of the high level of dealer support.”

The team then went on to prepare a detailed analysis of the venue acoustics. TEF analysis was among the first steps in exploring the options available to meet the client’s brief for evenly distributed speech and music without any ‘dead’ areas, and for high quality, clear sound with minimal reverberations. It demonstrated that a center cluster of high power, highly directional loudspeakers would serve to direct the sound into the seating areas without excessively exciting reverberations from the upper levels and the roof. This would be essential for clarity and intelligibility.

The technical solution settled on was a cluster of compact, high power Renkus-Heinz CT5 full-range loudspeakers, matched to Crest Audio PL Series amplifiers, a Community DSC24 loudspeaker controller and an Allen & Heath GL4000 console.

The CT5 loudspeaker is part of the CT Series and was chosen for the Jeonnam arena because of its close integration of the latest technologies developed by designer Ralph Heinz. These include TRue Array Principle (TRAP) enclosures to provide optimum coverage in tight-packed arrays; Complex Conic horns for accurate pattern control and natural reproduction; and the company’s CoEntrant Topology, which delivers high power from compact cabinets by integrating the outputs of mid and high drivers (in this case, the acoustic output of an 8” cone and a 1” compression driver) into a wideband, high power true point source that can be loaded with a single waveguide. The four CT5s were mounted in a steel cluster frame painted yellow to match the roof bracing with intermediate panels to conceal the cabling. “The combination of TRAP enclosures and the high directivity,” comments Ralph Heinz, “provided DaiKyung Vascom with the correct acoustic solution for the venue and allowed maximum power to be concentrated where it was required, with minimum expenditure and weight loading.”

The system was specified in mid-2003 and, after a month-long installation process, was commissioned in March 2004. Since then it has seen its multi-purpose design used to the full with a wide range of events staged at the Jeonnam arena. Mr Dae Hyun Han concludes: “The new system has met the client’s brief very successfully and we are all extremely pleased with its performance.”