Designing a System

1Determine the number of audio channels

You will need to order one LT-82 transmitter for each audio channel. The Listen system can deliver up to four audio channels simultaneously.

2Determine the room size and shape

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3Complete the room layout worksheet

&RPSOHWHWKHURRPOD\RXWZRUNVKHHWIRXQGLQWKHÀQDOVHFWLRQRIWKLVJXLGHSODFLQJWKHORFDWLRQRIWKH transmitters, power supplies and radiators using the worksheet key. The following factors will determine the coverage of the room.

3A Number of radiators and location

Except in small rooms it is recommended that at least two radiators be used to ensure good coverage and minimal shading. Listen radiators (when used with Listen receivers) will cover approximately 10,000 ft2

(929 m2) for one channel as indicated in the diagram below (note the coverage decreases as the number of channels goes up). For two channels, one radiator will cover 5,000 ft2 (465 m2) and for four channels, one radiator will cover 2,500 ft2 (232 m2).

Horizontal Plane Footprint Pattern (feet)

DesignDesign GuideGuide

Coverage pattern

shown in feet

50

40

30

20

10

0

10

20

30

40

50

4 TX

2 TX

1 TX

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

150

You should use the above coverage pattern to determine coverage of each radiator in your system, not by trial and error. The radiator will be stronger when new and therefore is under-rated by 40 percent and the coverage pattern above accounts for this. 40 percent degradation will occur after approximately 8,000 operating hours.

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Listen Technologies LR-42 Designing a System, Determine the number of audio channels, Determine the room size and shape