Loops can be fixed at various heights dependant on type and use. The one height they must NEVER be fitted is at the same height as the hearing aid as this causes massive fluctuations in signal loudness across the width of the area.
Perimeter loops are ideally installed at a height of 14% of the loop width (shortest dimension), above or below the listening plane. The listening plane is normally (for a seated person) assumed to be at a height of 1.2m (ie ear level). This gives two possible loop wire installation heights – one above and the other below the listening plane. So the ideal install height could be in the basement, at floor level or high up the wall, all depending on room width. High level loops can be installed in plastic trunking or fixed to or behind wooden or other decorative features. The loop cable can even be run externally or directly buried if a suitable grade of cable is used.
Array systems are almost always installed on the floor or in plastic conduit above a suspended ceiling. This is because the loop wire runs backwards and forwards across the width of the room a number of times in a specific pattern often called an array. The physical dimensions of each array are quite critical in terms of wire placement and spacing. An installation accuracy of within 50mm or better can be important when following drawings supplied by Ampetronic for an array layout. Arrays can occasionally be fitted in plastic conduit in the top surface of a screed layer.
Installation along steps in tiered seating or similar requires careful thought. Take a look at some of our recommended installation methods for steps.
At reception, ticket sales, and other counters, the usual loop arrangement is to have a pre-formed loop mounted vertically in the counter construction.
Other applications such as help points, public vehicles and even yachts in competitive events can benefit from using loop systems and typically require a custom design loop layout which can be provided by Ampetronic on request.