The
EOF
(End of Fall)
jack
is specific to Channel B. It outputs a gate that
goes high when the fall stage ends, and remains high until the envelope
begins rising. Said another way, the gate at the
EOF
jack only goes low
during the rise stage. The
EOF
light will shine orange when the
EOF
output is
high.
Audio In, Audio Out, and VCA CV Jacks
The
Audio In
and
Out
jacks are the input and output of the VCA. The
envelope output (pre-level and offset pots) is internally routed to the
VCA CV
input. When the envelope is stopped or at 0V, the
Out
jack will output silence.
As the envelope rises, the signal will get louder until it becomes as loud as
the input signal at the peak of the envelope. As the envelope falls, the signal
will fade back to silence.
Audio
In
B
is normalized to
Audio In A
, as
indicated by the graphics on the faceplate. So when
Audio In B
is
unpatched, the
Audio In A
signal will be sent to both channels. Patching into
Audio In B
will break this connection so that both channels are operating
independently.
When patched, the
VCA CV
jacks break the internal connection between
envelope and VCA, allowing for independent use of the VCA. The
VCA CV
input has a range of 0 to 5V, which translates to about -90dB (silence) to 0dB
(unity gain).
Trigger Jacks
Each
Trigger
jack requires a trigger of at least 2V to start an envelope. If
there is no envelope in progress, then a trigger will initiate a single complete
envelope. If the envelope is rising when a trigger is received, then the trigger
is ignored (unless the
RETRIG
jumper is installed, see below). If the envelope
is falling when a trigger is received, it will begin rising from its current voltage.
On the back of the module is a
RETRIG
jumper for each channel. When this
jumper is installed, the envelope will immediately jump to 0V and start rising
any time a trigger is received. This can cause a click on the VCA output, so
the jumper is not installed at the factory.
Follow Jack
The
Follow
jack is the input of a slew limiter, and can also be used for
complex envelope generation, exotic audio filtering, and envelope following.
Whenever the internal envelope is not triggered or cycling, the envelope
output will rise or fall in order to match the voltage level present on the
Follow
jack. However, the rate of rise and fall times is limited by the positions
of the
Rise
/
Fall
sliders and the CV amounts. That is, the envelope output will
try to “follow” the signal present on the
Follow
jack, but it can only rise and
fall as fast as the envelope would rise/fall if it were to be triggered. Since
“slew” is the rate of change, we call this “slew limiting”.
Slew limiting can be used to create complex envelopes (ASR, ADSR, etc) by
timing the signal on the
Follow
and
Trigger
jacks. See Fundamentals of the
Follow Jack on page 14 for more information.
Page of
5
20
Follow
Trigger
In
Audio B
Out
VCA CV
A
