Successful Bosch demo at Nicholson Museum
Published: ASIA
AUSTRALIA: The Nicholson Museum, which contains the largest and most prestigious collection of antiquities in Australia, has been equipped with a demonstration Bosch LA3-VARI-BH Vari-directional array speaker. In a building of great historic value, the room’s acoustics could not be modified and so Sydney-based consultants WSP Lincolne Scott were called upon to provide a solution for the Museum’s needs.
The Nicholson Museum is the country's oldest university museum, featuring masterpieces of ancient art and objects of daily life from Egypt, the Middle East, Greece, Rome, Cyprus and Mesopotamia. It currently exhibits art, jewellery, metal work and terracotta sculptures from the Etruscans, depicting them as the most powerful people in the Mediterranean around sixth century BC.
Background music in the museum is provided by 24 Electro-Voice C8.2HC ceiling speakers in the 16 x 22m main room, characterised by glass cabinets, polished hardwood floors and concrete walls. However, the classic shoebox shape of the room with a 4m ceiling height lacks any acoustic absorption, and this has further conspired to create a 3.5 second delay time. As such, the curator’s lectures and speeches delivered from a lectern were previously unintelligible for most visitors and in particular, for those with hearing difficulties.
Roneel Singh from WSP Lincolne Scott turned to Bryan Davidson from Bosch Communications to discuss using a demonstrational Vari-directional array loudspeaker, remembering that it was demonstrated very successfully at Infocomm 2010.
WSP were further engaged by the client to undertake Ease modelling for the space to review loudspeaker and acoustic options to improve the speech intelligibility in the space, and following extensive site measurements and modelling, the single LA3-Vari-BH was deemed the best solution.
Fixed to a concrete column at a height of 2m, the active unit was optimised via a Cat-5 ethernet network connection to a PC configuration program. The Vari Configuration Set includes configuration software and a USB to RS485 converter to connect a PC’s USB port to the Vari unit. This allowed all eight loudspeakers, which each come with their own class D amplifier modules and on board DSP, to be modified and directed individually in Ease with differently delayed signals towards the museum’s audience and away from the ceiling, walls and exhibits. The result is reported to be a very good direct to reverberant sound ratio.
To create an even sound level in the museum’s listening area, the shape of the beam was further optimised towards the listening plane. The 1.2m height LA3-Vari-BH performs this in the digital domain using the on-board DSP and multi-channel amplification, producing a consistent SPL from front to rear, with a minimum of side lobes. For larger listening areas, two larger models are available in 2.4m and 3.6m lengths, whilst an integrated ambient microphone sensor registers background noise levels.
When Mr Davidson later returned to the Museum to remove the silver gray demonstration unit, the curator asked him to leave it attached to the column so that it could be permanently fixed at a later date. The demo clearly creates the sale.