
10.2. THEORY 189
+
x[n]
y[n]
allpass
depth
+
x[n]
y[n]
notch
depth
Figure 10.13: Block diagrams of the phasing effect using an allpass filter or a notch filter.
Reverb is an effect that we hear every day and in most cases take for granted. One
proposed design [73] for a realistic-sounding reverb effect is shown in Figure 10.14. Modern
music studios add some amount of reverb to almost every recording to compensate for
consumers listening to the playback in relatively small rooms; without any added reverb
the recording would have a “dead” sound to it. Reverb is caused by a multitude of sound
+
z
R1
α
1
y[n]
x[n]
+
z
R5
α
5
+
+
1
+
z
R2
α
2
+
z
R3
α
3
+
z
R4
α
4
+
+
+
z
R6
α
6
+
+
1
+
α
7
comb filters allpass ...