MASTER AMPLIFIER
Attenuation in the voltage controlled amplifier (VCA) is controlled by Envelope Generator 1 and 2 via
the panning mixer (ENVELOPE MIX) and the VELOCITY CONTROL (CV2).
There are two attenuation control modes: Linear and logarithmic (Log).
In linear mode the attenuation follows a linear relationship; 1 volt increase (or decrease
)
of control
voltage amplifies (or attenuates) 20% of the incoming signal or expressed in a simple mathematical
formula:gain = X Volts/0.2
In the logarithmic mode attenuation = X Volts * 15 dB
The illustration below shows what the signals look like in the two modes.
Performance at maximum attenuation of audio signals is shown in the illustration below.
Time (milliseconds)
5.0
2.5
0.0
-2.5
-5.0
-7.5
50
100
150
200
250
300
7.5
O
U
TP
U
T
(V
ol
ts
)
MASTER AMPLIFIER OUTPUT,
AMPLITUDE MODULATED BY ENVELOPE GENERATOR
LINEAR MODE
LOG MODE
dB
V
rm
s
0.0
-10.0
-20.0
-30.0
-40.0
-50.0
-60.0
-70.0
-80.0
-90.0
-100.0
-110.0
900
950
1.0k
1.1k
Frequency (Hz)
Power Level = 0.31 dBVrms, VCA CV = 5 Volts
Power Level = -84.91 dBVrms, VCA CV = 0 Volts
1.2k
MASTER AMPLIFIER, ATTENAUTION RANGE
45
