Quad VCA Manual
v1.00
Controls
1. CV
Attenuator
-
Controls
the
amount
of
CV
modulation
sent
to
control
a
channel’s
level.
Because
the
CV
inputs
cascade,
if
there
is
no
CV
input
on
a
channel,
but
a
preceding
channel
has
a
CV
input,
this
knob
will
bring
up
that
previous
channel’s
CV
signal.
2. CV
LED
-
Each
of
the
four
channels
has
a
red/green
LED
whose
intensity
shows
the
post-attenuator
level
of
the
incoming
CV
signal.
It
lights
green
for
positive
voltages
and
red
for
negative.
3. Linear
/
Exponential
Response
-
This
attenuator
controls
the
response
of
the
channel’s
VCA
to
the
LEVEL
knob
and
CV
input.
When
fully
counterclockwise
the
response
of
the
channel’s
VCA
is
exponential.
When
turned
fully
clockwise
the
response
is
linear.
In-between
settings
provide
a
variable
response
between
the
two
extremes.
4. BOOST
-
When
this
switch
is
set
to
the
left
position
(disabled)
the
maximum
linear
gain
of
the
channel’s
VCA
when
the
LEVEL
knob
is
fully
clockwise
or
+5
V
is
applied
to
the
CV
input
is
approximately
unity
(1:1).
When
set
to
the
right
position
(enabled)
the
signal
is
boosted
by
around
+6
dB
(2:1).
5. LEVEL
1
-
Sets
the
base
level,
or
bias,
of
the
channel’s
VCA.
When
fully
clockwise
this
approximately
equivalent
to
applying
a
+5
V
voltage
at
the
CV
input.
In
the
fully
linear
response
this
results
in
unity
(1:1)
gain.
The
knob
level
is
summed
with
the
channel’s
CV
input.
6. LEVEL
2
-
Sets
the
base
level
of
channel
2.
7. LEVEL
3
-
Sets
the
base
level
of
channel
3.
8. LEVEL
4
-
Sets
the
base
level
of
channel
4.
Inputs and Outputs
A. CV
1
-
The
CV
input
for
controlling
the
level
of
channel
1.
A
+5
V
input
with
the
channel’s
attenuator
fully
clockwise,
response
knob
fully
linear,
and
LEVEL
control
fully
counterclockwise
results
in
approximately
unity
(1:1)
gain.
B. CV
2
-
The
CV
input
for
controlling
the
level
of
channel
2.
If
nothing
is
connected
to
this
jack,
the
CV
is
taken
from
CV
1
.
C. CV
3
-
The
CV
input
for
controlling
the
level
of
channel
3.
If
nothing
is
connected
to
this
jack,
the
CV
is
taken
from
CV
2
.
D. CV
4
-
The
CV
input
for
controlling
the
level
of
channel
4.
If
nothing
is
connected
to
this
jack,
the
CV
is
taken
from
CV
3
.
E. IN
1
-
The
input
to
channel
1.
F. IN
2
-
The
input
to
channel
2.
G. IN
3
-
The
input
to
channel
3.
H. IN
4
-
The
input
to
channel
4.
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