Distances With Equivalent Speech Transmission Index Values
Ceiling Array Microphone (Distance to Talker)
6 ft (1.83 m)
8 ft (2.44 m)
10 ft (3.05 m)
12 ft (3.66 m)
Data was collected in a typical huddle room with the following measurements:
•
Reverberation decay time: 500 ms @ 1kHz
•
Noise floor: 40 dB SPL (A-weighted)
Note: These values are specific to the described room. In a well-controlled acoustic environment, the array microphone may perform with equivalent Speech
Transmission Index values at even greater distances. In highly reverberant rooms, the performance is less predictable.
A = Distance between array microphone and talker
B = Distance between cardioid microphone and talker
In this example, the acoustic performance of the array microphone mounted (A) feet from the talker matches the car
dioid gooseneck microphone placed at a distance of (B) feet from the talker.
Cardioid Gooseneck Microphone (Distance to Talker)