This document discusses signal processing techniques for a cardioid array. It involves adding and subtracting delayed signals from three microphones or "subs" to create directivity patterns like a cardioid. The processing includes a 1/4 delay for one sub and inversion of another sub's signal.

1. s
t +/-
s tSubs1+3Sub2 +/-
t
t
Sub 2Sub 2
Sub 1Sub 1
Sub 3Sub 3
s
Prozessing
Sub 2
1. /4 Delay
2. invers
Cardioid-Array
So phis ticate d Audio Eng ine e ring