Marshall Day Acoustics Pty Ltd was engaged to provide acoustical consulting advice on the proposed new $120M Central City Studios at Docklands, Victoria.

We were engaged by Hassell Francis, a joint venture consortium between architect Kim Francis and Hassell Pty Ltd.

Central City Studios consists of five individual world class sound stages with a total floor area of 6,400sq metres on a 6ha site. The largest studio, Studio 1 has a floor plan of 40m x 60m with a floor to ceiling height of 20m at the highest point. Each studio is designed for full feature film production and Studio 1 includes a below ground pit for shooting of multi level scenes such as basements, attics or water scenes. Studio 5 is designed for use as a TV studio for live audience productions.

The studios are located very close to the Melbourne City Link Freeway, adjacent to an elevated section of road through the Melbourne Docklands district leading to the Bolte Bridge . Traffic noise from the bridge had a significant influence on the design given that the required traffic noise level within the building was below NR22 (25dBA). Of particular interest was the roof design which consisted of a floated roof mounted above the rigidly constructed ceiling.

Special elastomeric mounts were selected to provide isolation against external roof loads and wind loads in both directions. The resulting system required every mount on the project to be inspected and adjusted to comply with Marshall Day Acoustics' strict performance requirements. Marshall Day Acoustics provided advice on the vibration isolation of the floated floor slabs. These floors were a particularly critical issue given the unique vibration transmission characteristics of the Coode Island silt upon which the studios are floated.

The specification for the studios required that the air supply and return systems achieved a noise level less than NR22 in film mode which is at 50% volume flow. A unique feature of the studio design was the need to minimise the adverse visual impact of roof mounted plant. Consequently the exhaust fan chambers for each studio were internally mounted within the studio itself, achieving NR20 or less from fans exhausting directly out of the space, proved to be a significant challenge overcome by Marshall Day Acoustics using the separately mounted and isolated fan chambers.

Commissioning tests on the studios at 100% flow, 50% flow and no flow conditions, indicated that the level of traffic noise in most studios was below NR15 and for most studios at the design condition noise levels were NR20 and below in film mode. With a superb new film production facility in the heart of Melbourne , the new Central City Studios are assured of success, particularly with their superb acoustics and quiet environment ideal for today's high-tech quality film production.

"Hassell Francis worked with Marshall Day, experiencing excellent response times and consisient levels of reliability from their personnel...the outcome for these studios has been:

- an acoustic performance exceeding the strict specifications set by the State Government.

- a project delivered on time, on budget meeting the strict design standards set by the state government"

Tim Shannon & Kim Francis, Directors, Hassell Francis Pty Ltd