"Ampetronic performed a site survey at Easter of 2003," says Stage Electrics' Jonathan Porter Goff. "We'd worked with them before and we were very pleased to be working with people we trust." The main theatre can seat 1848 people, with a further 48 standing places, on three levels. "There is induction loop coverage everywhere except the side slips and the seating on the orchestra pit lift," explains Ampetronic system designer Richard Brooks. "As well as the problem with the structural steel, installing loops on multiple levels (stalls and two circles) is challenging, as the systems can negatively interact with each other. Our magnetic simulation software, designed in-house, was able to simulate the interaction between the levels by plotting the magnetic field three-dimensionally. The loop layout was then designed to minimise this interaction, whilst Ampetronic's 'Phased Array' approach to loop design means that the loss caused by the metal could be minimised. Other areas of the complex where Ampetronic loop systems are installed include the Studio, the Urdd Hall and the studios of the Diversions Dance Company.
To keep spillage between systems in adjacent rooms to a minimum, Ampetronic's low spill loop design approach was used, configured with its magnetic simulation software, attenuating the signal by at least 40 dB into the adjacent room - the magnetic equivalent of an acoustic partition between rooms. "Induction loops aren't a visible part of the workings of the WMC, but it's tremendously important to us that we provide not just any solution, but a solution that works well for our visitors with hearing disability, despite the complicated nature of our requirements."
(Lee Baldock)