Northern Light has just completed the installation of a very complex induction loop system as part of the £9 million refurbishment of Edinburgh’s prestigious Usher Hall. All the required Ampetronic equipment and accessories were supplied by Canford. Also installed was the very first production unit of the new Canford manufactured EMO CR32 remote switchers from the EMO Master Switchers range.
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Usher HallNorthern Light’s considerable experience in designing and installing complex, top notch induction loop systems was called upon by the consultants overseeing the massive refurbishment of the world famous Usher Hall in Edinburgh. The Victorian auditorium is a circular design and is a Grade ‘A’ Listed building and as such presented very specific barriers to the creation of a state of the art induction loop system.
The building holds a unique position in Scotland as the first to be constructed from reinforced concrete. The Circle and the Grand Circle are held in position by a cantilever construction, in effect, the sheer weight of the dome above them holds them in place. Whilst this means the listed status is most assuredly justified, it also means loops could not be installed in a typical fashion. Absolutely no channelling of the walls or lifting of the floors was permitted and there is very little area on the ground floor or Stalls area that is carpeted where a loop can be hidden underneath.
Northern Light’s project manager, Larry McGuire commented “The difficulties in working within a building which has attained Grade ‘A’ listed status cannot be over stressed. You could almost say we were working with one and a half hands tied behind our backs. It was compounded by all the rest of the renovation work being carried out at the same time which was providing new challenges on an almost daily basis.”
McGuire’s team would frequently trace existing cabling infrastructure to a ‘tie-in’ point only to find that whole wall or section of wall demolished and the cabling buried behind new blockwork.
After 2 days of extensive experimentation and measurement within the 1200 sq ft Stalls area it was concluded that nine loops would be needed. The each of the two circle areas were divided into four sections with a further loop running across at the front of stage. By carefully considering the phasing of each loop and getting them to complement each other they were able to achieve a 95% coverage of the auditorium despite there only being the single downstairs loop in the Stalls. This latter loop is actually two identical aerials powered by separate amplifiers.
EMO CM6 and CS6 Mains
Power Switching SystemsAnother feature of the system was a requirement for their remote operation and for sections of the overall system to be able to be switched on and off individually for test and maintenance purposes. This was achieved by use of an EMO CM6 Master Switcher in the central processing rack located under the main stairs and multiple uses of the EMO CS6 Slave Switchers in each of the remote racks.
The system can be powered up and down remotely by use of the new EMO CR32 Remote Keypad that duplicates the security keypad on the CM6 Master Station. The CR32 was designed to fit into a standard dual gang wall socket so it can be flush mounted to maintain a low profile, allowing it to be placed discreetly in most surroundings..
EMO CR32 Remote KeypadCanford also supplied a total of 14 Ampetronic ILD1000G Loop drivers and an Ampetronic ILR3 Loop receiver. For monitoring a Fostex RM-2 audio monitor was used and a Sonifex RB-DA6 distribution amp also featured. The majority of the cabling for the loops was by induction loop foil tape and the rest of the related audio cabling used several hundred metres of Canford’s own design Starquad type cables.
The work was completed in time for the main hall's re-opening for this years Edinburgh Festival with the venue featuring heavily in the classical music program.