A 700-seat auditorium with a semi-circular plan provides provided some interesting challenges for the AES team.

Whilst this layout is advantageous for the audience’s proximity to and view of the stage, the proposed layout for the Charles Luney Auditorium at St Margaret’s College in Christchurch was acoustically difficult, as lead acoustic engineer on the project Jeremy Trevathan explains – “The curved seating tiers and large curved back wall would have reflected sound back towards the stage – causing large variations in sound level over the audience area, and a very difficult environment for performers”.

Using 3D modelling, AES were able to determine how to control and direct the sound to optimise performer and audience experience, while retaining the semi-circular shape the Client and architect loved. This involved the use of a visually-impressive array of concentric timber reflectors above the stage and audience area, along with vertical reflectors to make the most of the auditorium side walls and ensure audience members felt ‘enveloped’ by the sound. Potentially problematic reflections and focusing from the curved rear wall were avoided by breaking up and re-orientating surfaces to distribute reflected sound evenly, rather than focus it all in one location, and through the use of acoustic absorption materials.

The facility opened in May 2013, providing a much-needed alternative performance venue for post-earthquake Christchurch and has seen a high level of use including as a venue for live television, and extensive use for Christchurch Symphony Orchestra and Chamber Music New Zealand events.

In a recent review, Ken Booth of Chamber Music NZ described the acoustics of the exciting new venue – “There is an uncluttered view of the stage; the acoustics are excellent; the soundboard over the stage ensures the sound goes throughout the auditorium; the seating is comfortable and there is no traffic noise. All the detail (of the performance) was audible because the auditorium made it so accessible to the listener. The new venue is ideal…”

The Forté Health building on Kilmore Street was one of the first major building projects in the city centre to get underway after the Canterbury earthquakes.

The building is a 3 level surgical hospital featuring state of the art patient and surgical facilities and seismic resilience was a key consideration in the design – particularly with regard to ensuring that the hospital could continue to function regardless of the circumstances.

This key issue flowed right through to the acoustics design for the building, with the AES team required to collaborate extensively with other members of the project team –in particular with Klein Architects who were responsible for the design of the building interior. As this building was the first building in New Zealand featuring Steel Press technology which allows the building to move with a seismic event, and then settle back into its original position, extensive seismic detailing was required where walls within the building met external walls and floor slabs. A variety of details were developed which allowed for significant relative movement in the building structure while not compromising on noise control between spaces within the building, including wall elements which could slide over each other, and the use of flexible barriers to seal gaps.  All of this meant that noise sensitive spaces such as operating theatres and recovery rooms could be protected, which a structural system providing 180 % of building code could still be employed.

The project also had a strong sustainability focus. As internal noise is a significant factor in terms of occupant satisfaction and wellbeing AES considered expected levels of noise throughout the building due to outside sources like traffic and rain noise, and inside sources such as air-conditioning systems. The building design and mechanical systems were then modified as required to ensure expected noise levels complied with the New Zealand Green Building Council requirements.  This work, along with many other sustainability initiatives, meant The Forte Health Building was New Zealand’s first  hospital to achieve a 4 Green Star rating.

Project Blue Sky is a significant and exciting project to redevelop the majority of Rangi Ruru site.

AES was called in to ensure appropriate acoustic engineering solutions were included in the Academic Precinct including Science and Technology Building, Gibson Centre learning centre / library, Visual Arts Building and the General Academic Building. Challenges of separating high and low noise activities, and providing appropriate internal environments for a wide range of activities were also met head-on in the design process for the Music and Drama School. Stages still on the drawing board include a swimming pool, sports pavilion, Intermediate School, School Hall and Performing Arts Centre.

This project was led by Senior Acoustic Engineer Tracy Hilliker who worked closely with Melbourne-based architects McIldowie Partners.  Tracy explains how it was great to work on a project which embraced a modern style of teaching and focused on providing flexible spaces – although this presented some new and interesting challenges – “As with all projects, it was absolutely essential to sit down at an early stage with the clients and project team, completely understand their needs, and vision for each space”.

Among the unique aspects of this project embraced by the AES team were a preference for exposed concrete ceilings with ‘cloud’ panels of acoustic absorption hanging below instead of traditional ceiling tiles, and the ‘Gibson Centre’ – a large circular library space and IT hub.

The outcome achieved by Tracy and the team within the ‘Collaboration Space’ associated with the Science and Technology Building in particular has gone beyond many peoples original expectations for the space, with the April 2014 Rangi News bulletin describing the revelation of the performance-quality acoustics of the space during the opening ceremony – “As guests took their seats the Kapa Haka group performed from the stairwell. The crowd revelled in the unexpected acoustics of the building and for some, thought turned to future opportunities for the building beyond the teaching and research of science”.