| Long time
delays are those that are 60 ms and more. |
| 1. With long delay, the
ear will hear the delay as an echo of the direct sound.
Adding delay creates what is known as a "slap"
echo |
| 2. When
feedback is added, the result is a repeating echo. |
|
|
| Slap Echo |
| Adding a
single repeat causes a "slap" of the instruments sound - a sound
that is often heard naturally at stadiums. It will give a
distinct "live" quality to vocals. Generally delay times
between 150 and 300 ms. are used. |
| Repeated Echo |
| Adding
feedback to a delay will generate repeated echoes. Usually slightly
longer delay times (between 200 and 400 ms) are used for this
effect. How long the repeating lasts depends on the amount of
feedback. Somewhere around 50% feedback the length of the repeat can
be made to be forever. Very high feedback values (above 50%) can
result in a feedback howl. |
| Timed Repeats |
| Slap or
repeated echoes contribute to the "thickness" of the sound but
can both get annoying as well as start to cover up syllables of a vocal
line. Timing the echoes to the tempo of the tune can allow more
repeating echo to be used, or a higher percentage of slap echo, without
annoyance. |
| In most
music, the steady even pulse of the music (called the "beat")
has a quarter-note value. At different tempos, the time of a beat will
change. The chart in Figure 4-14 (next page) shows the time of one beat
and 1/4 beat at different tempos. Using these delay times in the slap and
space echo effects reduces the irritation factor. One could also divide or
multiple these times by 2, 4, or 8 and get the same effect. To determine
the tempo one finds the "beat" and counts for one minute. |
| When you
adjust the delay time to be the time value of 1/8th note, 1/4 notes. 1/2
note or a whole note, the repeats blend into the music more but the
"thickening" quality of the delay remains in tact. You can
use the following chart to determine delay time values: |
|
DELAY TEMPO
CHART IN MILLISECONDS |
|
BPM
|
1 Beat (ms)
|
1/4 Beat (ms)
|
|
60
|
1000.0
|
250.0
|
|
61
|
983.6
|
245.9
|
|
62
|
967.7
|
241.9
|
|
63
|
952.4
|
238.1
|
|
64
|
937.5
|
234.4
|
|
65
|
923.1
|
230.8
|
|
66
|
909.1
|
227.3
|
|
67
|
895.5
|
223.9
|
|
68
|
882.4
|
220.6
|
|
69
|
869.6
|
217.4
|
|
70
|
857.1
|
214.3
|
|
71
|
845.1
|
211.3
|
|
72
|
833.3
|
208.3
|
|
73
|
821.9
|
205.5
|
|
74
|
810.8
|
202.7
|
|
75
|
800.0
|
200.0
|
|
76
|
789.5
|
197.4
|
|
77
|
779.2
|
194.8
|
|
78
|
769.2
|
192.3
|
|
79
|
759.5
|
189.9
|
|
80
|
750.0
|
187.5
|
|
81
|
740.7
|
185.2
|
|
82
|
731.7
|
182.9
|
|
83
|
722.9
|
180.7
|
|
84
|
714.3
|
178.6
|
|
|
BPM
|
1 Beat (ms)
|
1/4 Beat (ms)
|
|
85
|
705.9
|
176.5
|
|
86
|
697.7
|
174.4
|
|
87
|
689.7
|
172.4
|
|
88
|
681.8
|
170.5
|
|
89
|
674.2
|
168.5
|
|
90
|
666.7
|
166.7
|
|
91
|
659.3
|
164.8
|
|
92
|
652.2
|
163.0
|
|
93
|
645.2
|
161.3
|
|
94
|
638.3
|
159.6
|
|
95
|
631.6
|
157.9
|
|
96
|
625.0
|
156.3
|
|
97
|
618.6
|
154.6
|
|
98
|
612.2
|
153.1
|
|
99
|
606.1
|
151.5
|
|
100
|
600.0
|
150.0
|
|
101
|
594.1
|
148.5
|
|
102
|
588.2
|
147.1
|
|
103
|
582.5
|
145.6
|
|
104
|
576.9
|
144.2
|
|
105
|
571.4
|
142.9
|
|
106
|
566.0
|
141.5
|
|
107
|
560.7
|
140.2
|
|
108
|
555.6
|
138.9
|
|
109
|
550.5
|
137.6
|
|
|
BPM
|
1 Beat (ms)
|
1/4 Beat (ms)
|
|
110
|
545.5
|
136.4
|
|
111
|
540.5
|
135.1
|
|
112
|
535.7
|
133.9
|
|
113
|
531.0
|
132.7
|
|
114
|
526.3
|
131.6
|
|
115
|
521.7
|
130.4
|
|
116
|
517.2
|
129.3
|
|
117
|
512.8
|
128.2
|
|
118
|
508.5
|
127.1
|
|
119
|
504.2
|
126.1
|
|
120
|
500.0
|
125.0
|
|
121
|
495.9
|
124.0
|
|
122
|
491.8
|
123.0
|
|
123
|
487.8
|
122.0
|
|
124
|
483.9
|
121.0
|
|
125
|
480.0
|
120.0
|
|
126
|
476.2
|
119.0
|
|
127
|
472.4
|
118.1
|
|
128
|
468.8
|
117.2
|
|
129
|
465.1
|
116.3
|
|
130
|
461.5
|
115.4
|
|
131
|
458.0
|
114.5
|
|
132
|
454.5
|
113.6
|
|
Divide 1 beat by 2 for 1/2 beat |
| Divide 1/4 beat by
2 for 1/8 beat |
|
|