
218 Audio Effects: Theory, Implementation and Application
as being between the two loudspeakers. In between 1 ms and the echo
threshold, the sound appears to come just from whichever loudspeaker has
the least delay. More generally, the fact that for appropriate choice of delay
we perceive the two sounds as a single entity coming from the location of the
rst to arrive is known as the precedence effect.
–0.6 –0.4 –0.20 0.2 0.4 0.6
–30
–20
–10
0
10
20
30
Time Dierence (ms)
Perceived Azimuth Angle
FIGURE 9.4
Perceived azimuth angle as a function of time difference.
–30 –20 –10 0102
–30
–20
–10
0
10
20
30
Level Dierence (dB)
Perceived Azimuth Angle
FIGURE 9.3
Perceived ...