Case Study
Winnetka Congregational Church Needed to Fix Their Hearing Loop
Client: Winnetka Congregational Church (WCC)
Venue: House of worship with the spoken word and music.
Challenge: WCC asked Thunder Hearing & Sound to evaluate their existing hearing loop because they weren’t sure it was working as well as it could. Our evaluation showed that their existing system did not meet the IEC hearing loop performance standard and was inadequate for good speech understanding. To meet the IEC standard all signal levels should be between +3 and -3 dB. The existing system at WCC ranged from +5 to -11. These levels were not only too loud in some locations, but far too soft (about half as loud as it should be) in other areas. In addition, there was a null line (narrow area of no signal) within the seating area. The end result of this system was that a few seats sounded okay, but many were either too loud/soft. The previous installer tried to fix this with a new, more powerful hearing loop driver, but this resulted in levels from +10 to -6. Trading some seats that were too soft, for more seats that were too loud. It did not change the number of seats that were between +3 and – 3 dB.
Solution: Thunder Hearing & Sound offered to change the style of system to a phased array design with many more loops for much more even coverage that met the IEC standard. The existing system consisted of a design with two large loops and the new design utilized 10 much smaller loops with an overlapping pattern and new two channel phased array hearing loop driver. To install these wires, the grout between floor tiles was cut out and a special burial grade hearing loop wire was installed with new color-matched grout.
Results: The new system performs perfectly, with 100% of seats between +3 and -3 dB signal levels. The new design also eliminated the null line that was previously within the seating area. The new system allows a user to simply sit anywhere they want for great sound. With the correct design a user doesn’t need to question if they are getting a “good seat”, all seats are good. WCC was so happy with this new system they have since installed an additional hearing loop in their centennial social meeting room.
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