Audio Assist
Aug 31, 2009 4:26 PM
Powersoft amplifiers drive new sound system for Laugardalsvöllur National Soccer Stadium in Iceland.
Laugardalsvöllur National Soccer Stadium in Iceland
When it came time for a seating and systems update for the Laugardalsvöllur National Soccer Stadium in Iceland, systems installer EB Kerfi ehf chose Powersoft amplifiers to drive the EAW loudspeaker clusters. Considerations for the system arouse regarding proper coverage over a wide area, installing a system with enough power and clarity to handle multiple missions while offering remote controllable DSP to ensure even coverage and maximum performance throughout the stadium.
The Laugardalsvöllur National Soccer Stadium completely renovated its main seating area and built new office buildings onsite, prompting the desire to install a new sound system. The upgraded stadium now accommodates 15,000, with 9,800 permanent seats available in two covered main seating areas flanking the playing field and an additional 5,200 seating capacity on open-air concrete benches. The desire for the audio system was to deliver both highly intelligible audio for the announcers for the national soccer matches and support music productions.
EB Kerfi ehf specified a system that consisted of EAW loudspeakers driven by Powersoft amplifiers and interconnected with SommerCable wiring. The design of the loudspeaker setup was mainly done by Steve Badham at EAW. Hardware design and management was done by Einar Björnsson, general manager of EB Kerfi ehf with technical design, programming and measurements by Dagur Hilmarsson, technical director of EB Kerfi ehf.
In order to cover all the areas of the stadium, the decision was made to use six loudspeaker arrays, each with two cabinets flown from the roof system for the main seating with the addition of four speaker cabinets directed to cover the open air seating. Four Powersoft DIGAM K4 series amplifiers were installed to drive the high frequencies and four Powersoft DIGAM K6 series amplifiers were employed for the low frequencies in the bi-amped system.
The loudspeakers were special weather-protected versions of the EAW 5300 cabinets that offer a range of rotatable high-frequency horns to accommodate different dispersion patterns and 15-in. low-frequency drivers. Weather-protection features include a multilayer grill assembly of steel mesh and synthetic foam with a stainless steel perforated grill, enclosures constructed from exterior grade plywood coated with styrene resin, and a fiberglass shell with hatches and bolts sealed with non-hardening sealant. All drivers and transducers are designed specifically for outdoor applications. By specifying all EAW loudspeakers from one series, performance consistency was achieved.
Powersoft K4 and K6 rack
Whole space SPL and Axial sensitivity for the low-frequency section is 97dB at 62Hz to 1650Hz and 109dB at 1200Hz to 17kHz for the high-frequency section as typical with an output limit of 126dB average, 132dB peak for the low frequencies, and 131 dB average and 137dB peak for the high frequencies. Power rating is 800W at 8Ω for the low-frequency 15in. loudspeaker and 150W at 8Ω for the high-frequency driver.
The choice of Powersoft amplifiers was based not only on the crystal clear sound quality and the tight bass response, but it was also based on the extensive integrated DSP processing that allows for precise tuning of each loudspeaker cabinet for consistent performance and for the green-inspired efficient operational design. The remote programmable DSP on all DIGAM K-series amplifiers offer full, high-quality, onboard sound processing with up to 16 EQ filters per channel, up to two seconds of delay per channel for time correction between satellite loudspeakers, a peak limiter, and true power limiter for complete loudspeaker protection and crossover options. All amplifiers are connected to a computer where every part of the amplifier and all DSP functions can be actively monitored with reports automatically sent by email to the system administrator. Dagur Hilmarsson found that configuring the PA with Powersoft’s DSP interface was almost too easy. The patented damping factor and cable resistance compensation network offers a tight low end that is independent from cable section and length, perfect for the extensive cable runs for the stadium.
The K4 yields 900W of power per channel at 8Ω, while the K6 delivers 1300W per channel at 8Ω. The available power from the amplifiers insures adequate handling of transient peaks, while the protective circuitry prevents loudspeaker failure. Another advantage for this installation with Powersoft is that all K-series amplifiers take up 1RU and weigh only 26lbs. each, regardless of the power output. The ultra efficient design yields a 40-percent to 60-percent reduction in operational costs over traditional amplifier designs of equal output. This means the amplifiers not only use less power to operate, but produce less heat, reducing the need for cooling. The Laugardalsvöllur installation features a multistory booth in the middle of the main seating section. The amplifier control computer is on the ground floor as part of the announcer’s booth complex, while the amplifiers physically reside in the top floor to be closer to the loudspeaker arrays. Finally, the entire system was woven together though over 1000 meters of quad-core loudspeaker cables, 200 meters of analog audio cables, and 200 meters of Ethernet Cat-5 cables.
The system specified and installed by EB Kerfi ehf exactly matched the capabilities of both the loudspeaker system and the power amplifiers to yield a truly remarkable audio experience for the audience, prompting Páll Sævar Guðjónsson—main announcer for national soccer matches—to remark that the system sounds much better than he ever hoped for.
