Fig. 4.

Impulse response encodes the distance of the speaker to the microphone. An impulse response was recorded at the center of the arena (gray line). Black point represents sound onset, black empty circle is the estimated sound onset at the microphone׳s location. Time difference of these two points is called time-of-arrival of the sound, in this case it is 2.62 ms. It can be converted to distance by multiplication with the speed of sound: 0.00262 x 343=89.8 cm.