Feature: New build, old problems
Feature: New build, old problems
Richard Lawn visits Sydney’s Macquarie University, which is carving out more space for its growing student intake
As Australia’s intake of university students continues to soar, campus resources are becoming ever more stretched. Complete with its own railway station andoccupying 126 hectares of land, Macquarie is the fourth largest university in Sydney. Car parks and marginal sites are therefore making room for new faculties and facilities.
Designed as a unique supplementary venue within Macquarie, the Marquee was recently purpose-built to host a variety of post-graduation celebrations, exams, seminars and other events. Occupying the former car park, the multi-functional space challenged Macquarie University’s AVTS manager Darren Johnson to maximise the AV potential of this standalone space.
Designed primarily as a new ceremonial marquee, the venue can comfortably host 250 people. Constructed from Bondor-type insulation panels with a curved roofing structure, the building’s acoustic properties are further complicated by the glazed façade entrance, which the latest audio technology has helped to overcome. ‘Most of the campus combines Martin Audio O-Line speakers on the Q-Sys DSP platform,’ explains Johnson. ‘In terms of sonic performance, intelligibility, consistency and reliability, we have found this combination to be the best for all our educational requirements.’
Although the university’s core business is tuition, it perceived the potential to hire out the venue externally by connecting this to the existing Q-Sys PA system. Accordingly, Johnson invited mechanical and engineering consultantUmow Lai back to the campus to design an AV system that would fulfil the anticipated events within the Marquee. ‘The new building was constructed very quickly and so we didn’t have an enormous amount of time to draft our plans for the AV and lighting,’ explains Umow Lai’s senior ICT consultant, Jack Wilson, who heralds from the north-east of England. Working closely with Umow Lai and the structural engineer Fabritecture, Concept AV was appointed as the systems integrator for the project.
The decision to extend the Q-Sys platform to the Marquee prompted Wilson to invite QSC and Martin Audio distributor, Technical Audio Group (TAG), to provide an audio design for this space. Once TAG’s consultant liaison Bryan Davidson was provided with the room dimensions and building materials of the Marquee, the TAG team duly delivered a solution. ‘Flexibility was a key attribute for the multipurpose space, but the client also insisted on even SPLs with a flat frequency response,’ explains Davidson. ‘For example, when operating the room in exam mode, intelligibility is the overriding criteria for announcing clear instructions to students.’
The L-R Martin Audio O-Line arrays are mechanically optimised with double box resolution, with 20 O-Line elements per side receiving dedicated power and DSP from 10 QSC CXD8.4Qn amplifier channels. Providing low-frequency extension when required, three-per-side Martin Audio CSX112 subwoofers in cardioid mode are suspended behind each O-Line array. Serving as a pre-function area, the outdoor foyer receives announcements and BGM from L-R wall-mounted QSC AD-S10T speakers powered by a QSC SPA4-60 amplifier.
‘The micro line array elements provide software-optimised array configuration for focused sound energy and additional DSP-optimised functionality for increased coverage, consistency and control,’ continues Davidson. ‘This provides incredibly accurate focused beams away from the walls and, crucially, the rear glazing. When running in music mode, the audio is steered away from a front stage to minimise the risk of gain before feedback. The architecturally sympathetic design has promoted a discreet campus-wide deployment to date.’
‘Unlike many DSP “steered” columns, an O-Line array does not produce unwanted vertical side lobes,’ explains Wilson. ‘This is critical in reverberant environments as side lobes firing above and below the array simply add to the reverberant energy, impacting on intelligibility. O-Line’s ability to reproduce very high frequencies without side lobes makes it the ideal solution for both full-range speech and music reproduction in reverberant spaces.’
With its24 analogue audio channels, theQ-Sys Core 110f processor is capable of providing a 128x128-channel network. ‘With the Q-Sys platform, the Marquee can draw upon almost finite processing power,’ explains Wilson. The eight mic/line input connections at the rear of the QSC CXD8.4Qn amplifiers can also be used for additional inputs to the Q-Sys network. For a green university such as Macquarie, the amplifier’s energy-saving mode feature that ensures that the amplifiers draw minimal AC power was a great bonus. A Shure ULXD4Qquad-channel digital wireless receiver and ULXD1 digital wireless bodypack transmitter with handheld, head-worn and lavalier clip-on wireless mics round off the audio inventory.
Wilson worked closely with Johnson and the university team to both source and check whether standardised equipment such as Crestron control systems, Panasonic projectors and the Q-Sys Core DSP could operate together within this bespoke space. ‘Once we had made the checks, it was a case of seeking the correct screen sizes and elements,’ says Wilson. ‘The size and the shape of the room augured well for a L-R combination of Panasonic PT-RZ12K 12,000 ANSI lumens projectors. The dual Screen Technics high contrast grey 225-inch screens compensate for the ambient light entering through the rear wall glazing.’
Another main design category was for a hearing loop to be integrated for assistive listening needs. An infrared solution could not be adopted on account of cost. ‘It would mean stocking an inventory of up to 500 receivers and transmitters for a large function together with all the battery chargers,’ explains Wilson. ‘In addition, we didn’t want anyone requiring a neck-worn receiver to stand out in the crowd. A loop is much more discreet. Audio Brands was helpful in designing and providing a Univox PLS-X3 solution for the venue, while an AFILS hearing augmentation was installed within the concrete slab during construction.’
The integration of analogue and digital patchbays adds credibility to venue flexibility. A Dante audio network has been created from the back-of-house equipment rack to all the wall panel and floor box interfaces in the room. Connected by DM 8G cable and Cat-5e infrastructures, the floor panels incorporate HDMI and RGB/component video inputs, together with DigitalMedia 8G+ transmitters and multimedia interfaces, 2x1 AV switchers and connection to the Crestron DM switcher.
The portable, gently curved lectern is equipped with dual microphone inputs, a Shure MX418 18-inch gooseneck and a concealed cable management system for connection to any of the wall and floor plates. IncorporatingNeutrik male and female XLR connectors in addition to four BNC and four RJ45 data connectors, the wall input panels add to the venue’s flexibility.
Focusing their attention on the campus’ IT network, Johnson and his team insisted on the incorporation of a Cisco SF300-24PP 24 port PoE+ managed network switch. Incorporating an HD 8x4 switcher with a built-in scaler and microphone, a Crestron 4K DMPS3-4K-350-C presentation switcher integrates all the AV and lighting parameters for control from TSW-1060 10-inch and TSW-760 7-inch touchpanels in addition to several iOS touchscreens. ‘There’s no margin for error and so everything has to work quickly and efficiently,’ explains Johnson. ‘Our teaching spaces are running at 92–93% capacity most of the time, so downtime is unthinkable with so few overflow rooms available. The lecturers and users are familiar with the Crestron GUI and this makes the AV and lighting system simple to operate.’
‘The resultant AV design may bear all the hallmarks of other buildings within the university, but they all fulfil best-in-class features,’ concludes Johnson. ‘It’s not a cut-and-paste design. From the familiarity of the Crestron interface to the even consistency of the O-Line SPLs and the clarity of the Panasonic HD displays, the Marquee’s unique challenges have been mitigated. It’s one less building that I don’t need to worry about.’