Controls, inputs and outputs, 7 cv level 1 8 cv level 2 – AJH Synth MiniMod VCA User Manual
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DISCRETE CASCADED VCA
MASTER
CV 2
OUT
CV 2
CV 1
AUDIO 1
AUDIO 2
AUDIO 2
AUDIO 1
MASTER
OFFSET
mod
CV 1
2
8
4
6
0
10
2
8
4
6
0
10
2
8
4
6
0
10
2
8
4
6
0
10
2
8
4
6
0
10
2
8
4
6
0
10
11 Master (VCA 2) Level
1 Audio Input 1
5 CV Input 1
6 CV Input 2
VCA 1 Offset 9
Audio Level 1 3
Audio Level 2 4
Audio Input 2 2
Audio Output 12
Master CV Input 10
1 Audio Input 1 : Audio Input 1 forms part of a 2 input audio mixer which is attached to the front end of
VCA 1, this input is mixed with Input 2 at a level set by Audio 1 Level Control (3). Signal
levels of up to +/- 5 Volts are acceptable.
Note:
Just like the VCA on the vintage Model D synthesiser on which this module is based, the
input stage is AC coupled - therefore it is not possible to process DC control voltages
through the Audio Inputs - it is suitable for processing audio signals only. However, if DC
control voltages are accidentally connected to the Audio Inputs it will not cause any
damage to the module.
2 Audio Input 2 : Audio Input 2 forms part of a 2 Input audio mixer which is attached to the front end of
VCA 1. This input is mixed with Input 1 at a level set by Audio 2 Level Control (4). Signal
levels of up to +/- 5 Volts are acceptable. Should more Audio inputs be needed a
Eurorack compatible audio mixer can be connected to either Audio Input 1 or 2.
3 Audio Level 1 : Sets the amount of signal from Audio Input 1 (between 0% and 100%) that is mixed with
Audio Input 2 and sent to the Input of VCA 1.
4 Audio Level 2 : Sets the amount of signal from Audio Input 2 (between 0% and 100%) that is mixed with
Audio Input 1 and sent to the input of VCA 1.
5 CV Input 1 :
Control voltage Input for VCA 1, this is mixed with CV Input 2 (6) and the sum of these
voltages control the gain of VCA 1. An input voltage range of +/-5 V is acceptable and +5V
gives approximately unity gain. Negative voltages will generally be ignored unless
combined with a (larger level) positive voltage from CV Level 2 control, in which case the
resulting voltage will be (CV2 - CV1). The output of both VCA 1 and VCA 2 repond in a
linear manner in relation to all CV inputs.
Controls, Inputs and Outputs
7 CV Level 1
8 CV Level 2