Lexicon
20
Using the 20/20 AD
0dB
-3dB
-6dB
-8dB
-10dB
-12dB
-14dB
-16dB
-18dB
-20dB
-22dB
-24dB
-26dB
-30dB
-36dB
1
1.50:1
1.20:1
1.14:1
1.11:1
1.09:1
1.07:1
1.06:1
1.06:1
1.05:1
1.05:1
1.04:1
1.04:1
1.03:1
1.02:1
2
3.00:1
1.50:1
1.33:1
1.25:1
1.20:1
1.16:1
1.14:1
1.12:1
1.11:1
1.10:1
1.09:1
1.08:1
1.07:1
1.06:1
3
4
4.00:1
3.00:1
2.00:1
1.66:1
1.50:1
1.40:1
1.33:1
1.28:1
1.25:1
1.22:1
1.20:1
1.18:1
1.15:1
1.12:1
5
4.00:1
4.00:1
2.66:1
2.00:1
1.71:1
1.55:1
1.45:1
1.38:1
1.33:1
1.29:1
1.26:1
1.23:1
1.20:1
1.16:1
6
4.00:1
4.00:1
4.00:1
2.50:1
2.00:1
1.75:1
1.60:1
1.50:1
1.42:1
1.37:1
1.33:1
1.30:1
1.25:1
1.20:1
7
4.00:1
4.00:1
4.00:1
3.33:1
2.40:1
2.00:1
1.77:1
1.63:1
1.53:1
1.46:1
1.41:1
1.36:1
1.30:1
1.24:1
8
4.00:1
4.00:1
4.00:1
4.00:1
3.00:1
2.33:1
2.00:1
1.80:1
1.66:1
1.57:1
1.50:1
1.44:1
1.36:1
1.28:1
9
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
2.81:1
2.28:1
2.00:1
1.81:1
1.69:1
1.60:1
1.52:1
1.42:1
1.33:1
10
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
3.50:1
2.66:1
2.25:1
2.00:1
1.83:1
1.71:1
1.62:1
1.50:1
1.38:1
11
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
3.20:1
2.57:1
2.22:1
2.00:1
1.84:1
1.73:1
1.57:1
1.44:1
12
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
4.00:1
3.00:1
2.50:1
2.20:1
2.00:1
1.85:1
1.66:1
1.50:1
4.00:1
2.00:1
1.66:1
1.42:1
1.33:1
1.27:1
1.23:1
1.20:1
1.17:1
1.16:1
1.14:1
1.13:1
1.11:1
1.09:1
GAIN
THRESHOLD
As both the formula and the table show, raising the threshold increases the ratio
— making the compression more audible above the THRESHOLD setting.
However, because signals below the threshold are boosted linearly through the
compressor, raising the threshold may decrease the amount of time the
compressor is reducing gain. This may decrease the audible artifacts.
Conversely, if you lower the threshold all the way to -36dB, you will pretty much
guarantee that all but the quietest signals will experience some amount of gain
reduction, but the ratio will be so small (1.2:1) that the total effect may be less
noticeable than a higher threshold setting.
Start with RELEASE time set to about 180 mS, then shorten the time for
percussive program material and lengthen it for material such as voice.
RELEASE times of 0mS to
∞
are available. Attack time of the compression is
automatically set as a function of the signal rise time.
Compressor Knob Values
6
GAIN
(in dB)
8
10
12
4
2
0
-14
-10
0
-36
-18
-22
-26
100
560
THRESHOLD
(in dB)
RELEASE
(in mS and S)
-6
1
3
5
7
9
11
-3
-8
-12
-16
-20
-24
-30
180
320
1S
1.5
∞
56
32
18
10
5
0
Note that changing the settings of GAIN and THRESHOLD while recording may
produce audible clicks. If, for artistic reasons, you wish to turn the compressor
off during a recording, do so by increasing the release time to
∞
. (Using the
compressor on/off switch may produce a click.)