New Zealand - When North Harbour Stadium in Auckland approached Marshall Day Acoustics to propose a new sound system for their 12,000 seat grandstand, expectations were high. Having suffered 10 years with a budget-driven and ageing system and looking to secure the stadium's future as a nation-leading outdoor arena, the new sound system had to be capable and flexible enough to cater for all possible audience and event requirements, and be future proof to suit its expansion plans.

Enter Audio Telex in conjunction with Marshall Day, who developed a comprehensive state-of-the-art design using EASE acoustic simulation software and based around Renkus-Heinz loudspeakers.

This is the first major Renkus-Heinz stadium sound system in Australasia and stadium marketing manager Chris Kemp comments, "We don't want to tell people we have a new sound system, we just want them to hear the difference when they walk into the stadium."

North Harbour Stadium was built in 1997 as a multi-purpose outdoor sports and entertainment venue, holding up to 25,000 people in the burgeoning Auckland suburb of Albany. As well as hosting large concerts, it is also the home to Rugby Football's North Harbour team, and regularly hosts high profile international sporting and entertainment events. The grandstand complex also doubles as an impressive conference and function venue.

The 12,000-seat, three-tiered, half-shell-roofed grandstand posed some major challenges to the audio designers. Without careful calculation, gaps and hot spots would appear in sound coverage when the stand was in full flight, and the open design dictated weather resistant loudspeakers as well.

The Renkus-Heinz CDT520 was selected as the most suitable mid-high speaker. The lightweight device features a high power 10" MF and 2" HF mid-high speaker in a skeletal, cabinet-less frame. It also provided the required IP rating without the additional cost of fibreglass IP-rated enclosures for the mid-highs.

The low frequency cabinets and components, meanwhile, were weather treated and fibreglass coated by Renkus-Heinz and, like the CDT520s, are rated to IP559.

Five clusters, each containing a CELK15-2KW dual 15" low frequency cabinet and three CDT520 10"/2" mid- high horn speakers, achieve maximum intelligibility, even coverage and very high output if required.

Bartons Sound of Auckland supplied and installed the system. The company had previously been involved in the on-field PA which had also included Renkus-Heinz speakers. Murray Dick, operations manager for the stadium, comments: "It's quite funny - the only thing we kept from the old sound system was the same brand of speakers that are used in the new installation."

Three Lab.gruppen C48-4 power amplifiers and two C68-4s provide over 20,000W of amplification both to the Renkus-Heinz loudspeakers and the under-balcony fill loudspeakers. The four channel amplifiers were zoned to allow the clusters' different sections to be adjusted during commissioning. Bartons also made use of the amplifiers' in-built NomadLink port, and supplied a Lab.gruppen NLB60E network bridge that provides key amplifier functions such as remote power on/off, power sequencing, amplifier status and muting specific channels or groups via Ethernet from a PC or control system.

The entire system is controlled by a MediaMatrix Nion n3 DSP audio processor allowing specific tuning of individual loudspeakers, crossover points and particular voicing for the Renkus-Heinz clusters and balcony fill. A MediaMatrix CAB provides a CobraNet link between the NION and the Lab.gruppen amplifiers.

(Jim Evans)


Latest Issue. . .