The Auckland Town Hall is one of Queen Street’s most prominent historic buildings and listed by Heritage New Zealand. It operates as a multi-functional venue, with a world class performance hall.
The Great Hall is its centrepiece, seating up to 1,529 people in theatre-style on three levels. Designed for live performances, it includes a 17 metre stud and permanent concert platform. To ensure an exceptional audio experience for patrons with consistent, reliable sound coverage, the Great Hall received an audio upgrade to a JBL Professional high performance audio system. Auckland Live contracted Liquid Automation for the supply, programming and installation of the system.
Liquid Automation’s Commercial Sales Team noted that there were several important considerations when contemplating the design for this audio system, which were re-enforced by their customer Auckland Live who had very high expectations for its performance.
Firstly the heritage status – any system would need to be approved by the heritage panel so that it could not be any more obtrusive than the existing system and the Loudspeakers had to blend in with the existing colour scheme and overall look of the reflector panels.
Secondly the system must be easy to use for day to day operation as the Town Hall is a multi-use venue and the operators needed to be able to reconfigure the system to allow any combination of speaker zones to be activated, and it should be configurable as delay support for temporary PA systems when required.
The technical considerations included the redesigning and installation of new speaker brackets within the permitted loading limits, providing consistent sound coverage across the three vertical levels of seating, achieving good speech intelligibility from the audio system within a reverberant venue, fixing historical issues with noise in the audio chain caused by the mains power supply in the venue, the long cable runs between amplifiers and speakers and, the long analogue cable runs between the operating positions and amplifiers.
With a building of this heritage, three design approaches were considered: firstly a Line Array solution (JBL VTX), secondly a Steerable Array Column solution (JBL Intellivox) and thirdly a Point Source Cluster solution (JBL PD – Precision Directivity).
Careful consideration was given to each approach including in-depth modelling and system design. After a detailed review of all options the JBL Precision Directivity Point Source Cluster was considered to be a highly effective approach.
The PD6322 Full Range Three-Way Loudspeakers and the PD6212 Full Range Two-Way Loudspeakers allowed excellent vertical and horizontal pattern control and, good bandwidth response down to 40hz (PD6322) as well as the ability to precisely aim the cluster and in keeping with the aesthetic of the previous system.
Liquid Automation’s Commercial Project Manager and Shore Engineering Ltd co-designed the main central cluster array bracket to allow fine adjustment “pan/tilt” of every speaker in the cluster. The speaker angles were set in precise alignment in accordance with the computer modelling.
“The versatility of the system has reduced the need to install temporary sound reinforcement systems for events.”
To complement the PD central cluster, JBL Application Engineered Series AC16 two way compact loudspeakers were installed under the balcony areas and were also used for stage fills and delays. The AC16 speakers offered high output and high fidelity which was required for the system brief of a multi-use sound system.
JBL CBT70J Constant Beamwidth Technology™ Two Way Line Array Column speakers were used for Circle delays. “The asymmetrical vertical coverage of these speakers sends more sound towards the far area of room to make front-to-back sound levels more consistent,” says Paul Edlin, Audio Designer at JPRO. “This made these speakers the perfect choice for the circle delays.”
Dante Audio was enabled using BSS BLU Processors allowing for a noise free digital backbone of up to 128 channels between the three critical locations – the control booth, the lower plant room below stage floor and the upper amplifier rack in the town hall roof.
All three were connected via fibre optic cable. The BSS Soundweb network provides complete routing options between all three locations as well as automated scenes to enable any combination of speakers to be turned on or off which allows for maximum flexibility.
“The asymmetrical vertical coverage of the CBT70J sends more sound towards the far area of room to make front-to-back sound levels more consistent; this made these speakers the perfect choice for the circle delays.”
Using Harman’s own HiQnet Audio Architect control software, Liquid Automation provided an elegant user interface using a touch screen PC to help the operator quickly and easily switch between the required modes to fine tune the setup. Audio Architect gives the system administrator one software platform to help manage and control the critical components in the system in real time including BSS Soundweb (routing), Crown ITech amplifiers (main cluster) and Crown DCI Amplifiers (all delay speakers).
Continuing on with a need to make the system fully digital, the Digital Mixing Console chosen was the Soundcraft Si Performer as it allowed direct connection to Soundweb (via Dante) while also allowing a fibre optic stage box to be run to the stage for additional patching (via Madi).
Auckland Live Technical Operations staff and clients have commented on the excellent audio in the Great Hall. “The versatility of the system has reduced the need to install temporary sound reinforcement systems for events. Back-up and support from JPRO through initial teething issues has been excellent.”
