4ms EnvVCA, Руководство пользователя

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into the Follow jack, then a short gate width would only produce a complete envelope if the rise time
parameter was very fast. Gates that are more shorter than the rise time will result in an envelope that
doesn’t reach the peak, as seen in Figure 6 of the previous section. However, by patching the gate into
both the Trigger and Follow jacks, we get complete envelopes regardless of the settings, as seen in
Figure 7. Notice the width of the pulses and how they correlate to the sustain of the envelope output.
The first pulse is not wide enough to produce any sustain because its width is lesser than the time it
takes for the envelope to rise.
ADSR Envelope
An ADSR (attack-decay-sustain-release) envelope is like an ASR envelope, except that it adds a fourth
stage known as “decay” after the attack stage. After hitting the peak, an ADSR envelope “decays” to a
sustain level less than the peak level. See Figure 8.This sustain level and the speed at which the
envelope decays are controllable.
We can generate an ADSR envelope with the Dual EnvVCA by feeding a gate into Follow . The gate
should be generated by an external module such as a keyboard or sequencer that lets you control the
pulse width. The pulse width determines the length of the sustain, that is, the ADSR envelope will do
the attack and decay segments and then hold at the sustain level until the gate goes low. At that point
it’ll do the release segment.
Use a mult or stackable cable to patch the gate signal into Channel A’s Trigger jack and Channel B’s
Follow jack. (The diagram above shows it also going to Time CV , but ignore that for now). Patch Env
Out B to Channel A’s Follow jack. Both Cycle buttons should be off. You can take the ADSR envelope
out from Channel A’s Env Out jack, and/or you can run audio through Channel A’s Audio In/Out jacks.
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Rise Fall
Rise Fall Rise Fall
Level
Rise Fall
Cycle
Follow Follow
Trigger
Time CV
Rise Fall
Time CV
EOR
In In
Fall Rise
Level
Offset Offset
Slow
Fast
Slow
Fast
Audio B
Out Out
Audio A
A B
VCA CV VCA CV
Trigger
B
EOF
ENV
OUT
OR A
Env
Out
Slow
Fast
Med
Slow
Fast
Med
Dual EnvVCA
A
Cycle off
Rise adjusts attack
Fall adjusts decay
and release times
To mixer/output
amp
From sound source
Channel B Level controls
sustain level
Fall CV adjusts
decay time relative
to release time
Gate (pulse width
controls sustain
period)
Cycle off
Rise and Fall sliders
and switches to Fast