5.3
The Synth View
51
behaves in exactly the same way as the
Vel
parameter associated with the
Attack
knob.
Shape of the Envelope Segments
We have so far determined the shape of the envelope by adjusting the duration of the different
phases as well as their level. The envelope signal can further be modified by adjusting the shape
of the envelope segments. These are linear when the
Exp
button is in its
off
position and become
exponential when it is switched
on
as shown in Figure 29.
Free Run Mode
The
Free
button sets the envelope into free-run mode. This allows one to bypass the sustain phase
of the envelope or in other words, to go directly from the decay phase to the release phase regardless
of the amount of time a key is depressed.
Legato Mode
This mode is used to choose how the envelope generator reacts when a new note is played before
the end of the preceding one. When this occurs, two strategies are possible. The first one consists in
triggering a new envelope, from the attack phase, when the new note is played. The second consists
in applying the current envelope signal of the first note to the second note which produces a legato
effect. The first strategy is adopted when the
Retrig
button switched
on
while the second is applied
when it is in its
off
position. Note that when the keyboard is in polyphonic mode and the envelope
generator in retrig mode, the envelope generator behaves in a monophonic manner, reacting to a
logical OR between all the gates signal from the different notes played on the keyboard. In other
words the envelope generator is only triggered by the first note played on the keyboard and then
remains in the sustain stage until the last note is released.
Loop Modes
The envelope generator features three loop modes:
AD
,
ADR
and
Once
. These modes allow the
envelope to cycle between several stages of the envelope until the key is released and are selected
from the
Loop
drop-down menu.
In the
AD
mode, the envelope begins with the attack and decay phases as usual, but rather than
holding the sustain level, it repeats the attack (from the sustain level) and the decay phases until
the note is released. When the note is released the envelope signal returns to zero following the
release phase. The
ADR
mode is quite similar to the preceding mode and only differs in that the
looping is done by cycling trough the attack, decay and release phases. Finally, in the
Once
mode,
the envelope is played normally but the envelope generator cycles once more through the attack
and release phase when the key is released.
