Quad VCA Manual
v1.00
Instructions
4 Independent VCAs
The
simplest
way
to
use
the
Quad
VCA
is
to
ignore
any
of
the
cascading
CV
and
mixing
functionality
and
just
use
it
as
four
independent
VCAs:
● Connect
the
output
signal
from
the
source
to
IN
1
.
The
source
can
be
anything,
any
oscillator,
LFO,
envelope,
or
any
other
audio
or
CV
generator.
● Connect
OUT
1
to
the
input
of
the
destination.
● Connect
a
modulating
signal
to
CV
1
.
The
modulating
signal
can
also
be
anything
but
is
typically
the
output
of
an
envelope
generator
or
LFO.
Interesting
effects
can
be
had
when
using
audio-rate
sources
like
oscillators.
● Turn
LEVEL
1
fully
counterclockwise
to
remove
any
CV
bias.
● Adjust
the
CV
input
attenuator
and
Linear
/
Exponential
Response
control
to
taste.
You
can
repeat
the
above
instructions
for
channels
2,
3,
and
4
to
get
four
totally
separate
VCAs.
Level Bias
The
LEVEL
control
of
each
channel
can
be
used
bias
the
channel’s
response.
In
this
way
you
can
set
the
“default”
amount
of
signal
passing
through
the
VCA,
and
then
adjust
it
using
external
CV.
One
situation
where
this
is
useful
is
when
controlling
amounts
of
modulation.
For
example
when
the
output
of
one
oscillator
is
being
connected
to
the
FM
input
of
another
the
Quad
VCA
can
be
used
to
vary
the
FM
amount:
● Connect
the
sine
output
of
oscillator
1
(the
modulator)
to
IN
1
of
the
Quad
VCA.
● Connect
OUT
1
of
the
Quad
VCA
to
the
FM
input
of
oscillator
2
(the
carrier).
● Use
LEVEL
1
to
set
the
FM
amount
(index).
● Connect
an
envelope
to
CV
1
and
adjust
the
attenuator.
The
envelope
can
now
be
used
to
vary
the
FM
index
during
each
note
played.
Cascaded CV
The
Quad
VCA
features
cascading
CV,
meaning
that
one
CV
input
can
be
used
to
control
more
than
one
channel.
If
a
channel’s
CV
input
is
left
unconnected
then
the
channel
will
respond
to
CV
from
the
previous
channel,
subject
to
its
own
CV
attenuation
level:
Page
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